Gravity deniers and the gravity of ignorance
Douglas Adams, in his Hitchiker’s Guide to the Galaxy books, once suggested that falling was akin to an ingrained habit. If you could just forget about falling, you could defy gravity and fly. It works as a joke, but in real life gravity is pretty unforgiving.
So you can imagine my surprise when I came across “gravity deniers” trolling at Tara Smith’s Aetiology blog. Tara was dumbfounded that anyone could deny the so-called “germ” theory of infectious disease, since there has been so much evidence since Louis Pasteur’s time that bacteria, viruses, and single-celled parasites cause a wide variety of illnesses. Yet, it seems, just as there are souls who deny the connection between HIV and AIDS or the validity of the theory of evolution, there are some who deny that “germs” cause disease.
Woof.
One of the commenters, jspreen, claimed that poverty caused disease, noting that poor people seem disproportionately more susceptible to infectious diseases than richer people. Someone else claimed that Pasteur had recanted his support of the germ theory on his deathbed. I commented that jspreen was confusing correlation with causation, and closed my comment with this snarky remark:
By the way, I heard that Newton confessed on his deathbed that gravity did not exist. He was dreadfully sorry he ever came up with the idea.
Little did I know that my snide remark would end up hijacking the thread. To wit, here is what a germ-denier named Wilhelm had to say:
Who wants to deny gravity? I do. There IS no gravity force, and Newton had it wrong. Just take a bag holding 10 pounds of whatever, and hold it with your arm stretched out in front of you. After a while, your arm muscles get tired. Not surprising, because you expended energy, resisting gravitation. But… what is the energy source that is responsible for this “gravitational force”? Shouldn’t that get depleted also? (Think of the 1st Law of Thermodynamics)
The earth has been around for a long time. If there was any energy depletion, we should have measured that somehow.
So what’s a force for which there is no energy source? Answer: A non-existing force.
Now, there are so many confused thoughts in those few sentences that it might take an entire course in physics to untangle the mess. I resisted the temptation to reply — difficult for a physics teacher.
Then after a few more comments more pertinent to Tara’s original post, a commenter named dot weighs in on the subject:
denying gravity - Is there anywhere to debate this? It looks fun.
For example: could, rather than being a ‘force’, gravity be the effect a mass has on spacetime (like the general relativity theory or gravity). If this is the case, rather than an object ‘falling’ (as in moving toward the ground due to gravity), the distance between the ground and the object could be getting smaller due to mass ‘bending the universe’: Objects we perceive as being held still are actually moving away from the ground at the same rate as the distance between the object and the ground is shrinking.
Of course this would also mean that unless another force is acting upon everything (i.e the force of big bang), the universe would be shrinking, not expanding.
Thats my theory anyway - its probably already been disproven.
Now dot comes closer to understanding the physics than wilhelm, but she’s still missing the barn by a country mile.
robster and I attempted some basic physics instruction at this point, but dot was unconvinced.
So then, wheatdogg & robster, where does the energy expended to keep the object from falling go? What form does the energy used take? After all, energy doesn’t just disappear.
Gravitational Potential Energy doesn’t account for objects that remain a static distance from the ground: the potential energy does not increase.
The graviton particle model may or may not explain it: that particles move between the object and the ground MAY indicate that the energy the arm expends increases the mass of the object, which in turn is transferred to the ground in the form of graviton particles. This could indicate that the mass of the planet is increased by gravity.
This is, of course, all conjecture as the theory of gravity provides good predictions but we do not currently know why it works.I’m not getting into discussing ‘intelligent falling’ as, even if we can prove how gravity works, the religious people will just say thats god’s method for doing it just like with evolution: the single, universal and indisputable cause for everything approach.
(”Intelligent falling,” by the way, refers to an article in The Onion satirizing intelligent design.)
And later on,
Robster, what I meant by objects remaining a static distance from the earth was when you hold them at a static distance. If the energy is used for work and some is lost as heat, what work is that energy being used for if the object is being held at stationary distance from the ground, as the energy in the object is not changing (as Davis pointed out) but energy is being lost by the arm. Is it all heat?
Davis, that doesn’t answer Wilhelm’s point which I was referring to: why does your arm get tired after holding up a 10 pound object for a while? Where does that energy go if there is no change in that of the object?
Robster offers some more clarification, and then dot replies:
Robster,
The arm works to hold the object, I’m not disputing that. What I am questioning is where does that kinetic energy go/what does it do if the object is not moving (i.e being held still). Yes muscle fibres move, but the kinetic energy doesn’t stop there.
Working from the assumption that gravity is a ‘force’ that pulls things toward it, the kinetic energy would go to counterbalancing that ‘force’.
My theory is that gravity, rather than pulling things toward it, it bends space so that the distance between the source of gravity and the bag is constanty getting smaller. The kinetic energy would be used to move the bag away from the ground rather than hold it in the same place, but would have the overall effect of keeping it in the apparent same place.Either way you get tired and the bag does not fall.
(note: the “is it all heat?” comment was sarcasm (when in Rome, do as the Romans do))
As for the hook, I’ll work out an explanation, elasticity might be a good place to start.
Robster and I each posted another comment after dot’s last one, but I decided to work up a post here about the whole gravity denial thing.
Wilhelm seems to be a classic denier of all current scientific thought, be it germ theory or the standard model of particles and interactions. His convoluted comment tangles up fuzzy understandings of energy, thermodynamics, forces and gravity into a mush. Since he cannot reconcile his fuzzy understanding of physics as it is, he concludes that it must be wrong.
Dot, on the other hand, is not a denier, but a “misunderstander.” She’s got some of the concepts down, but imperfectly, so she can’t see the contradictions in her own explanations. She’s on the physics “short bus,” while Wilhelm just missed it entirely.
I suspect they are not alone. The American Association of Physics Teachers (AAPT), about 20 years ago, reported that less than 20% of high school graduates nationally had taken a course in physics before graduation. (The rate is now closer to 30% — still no great shakes.) Presumably, the other 70-80% may have had some physical science in middle school or in the 9th grade, which guarantees that they remembered none of what they were taught by the time of their graduation.
Physics is a tricky subject to teach. Like math, it can be very abstract while describing some very concrete things. We expect students to master physics in a year, but the truth is few students really understand the subject well enough after one course to discuss it authoritatively. They remember bits and pieces, and in time the bits and pieces get jumbled up with ideas pulled from other sources of information. We can well imagine how blissfully entirely unaware of physics concepts that other 80% is.
Energy is one concept in physics that has gotten completely fouled up by the popular press and new-age thinkers, who equate it with all sorts of esoteric, mystical concepts. Popular treatments of Einstein’s relativity, while usually very well done, leave some readers and viewers with a vague sense that gravity is an illusion, a result of the curvature of spacetime by massive objects like Earth, and that Newton had it all wrong.
So, Adams’ suggestion of forgetting about falling is a wry comment about that fuzzy concept of gravity-as-illusion. Einstein, though he suggested gravity was not per se a force, never recommended that people try to deny its effects. Things fall. Gravity sucks. It’s as easy as that.
Wilhelm, meanwhile, mangles the concept of energy to suggest that there must be some energy source powering the gravitation pull of Earth, much as burning gasoline powers a car’s engine. Since it appears Earth gets its “gravity power” from nowhere, a violation of the First Law of Thermodynamics, he concludes that gravity does not exist as a force.
If Wilhelm is correct, his feet need never touch the ground. He can fly around with Superman.
Dot later on also betrays some fundamental misconceptions about energy, forces and gravity, as well as a passing familiarity with general relativity. So robster and I tried to tutor her, perhaps with some success. We’ll see.
Physics (and I try to get my students to understand this subtlety) is a model of the “real” universe. Since Galileo’s and Kepler’s days in the early 1600s, we have built up a model of the universe that holds up remarkably well. Newton and Einstein had two diametrically different models of how gravity works, and the truth of the matter is that we still do not understand gravity as well as, say, magnetism.
Newton conceived of particles exerting forces on one another, either by contact or across distances, like gravitation. His laws of motion were a powerful tool in understanding how the universe works, but Newtonian physics has its limitations.
After Newton’s death, several scientists developed another model for the behaviour of the universe, the concept of energy. Unlike the nearly immediate acceptance of the Newtonian model, it took nearly 150 years for science to embrace the energy theory as valid. The “energists” had to accumulate sufficient evidence that their energy model gave the same results as the Newtonian model — the correspondence principle that knits the various fields of physics into a coherent whole.
Energy is defined as the capacity to do work. Work is the product of a component of a force moving an object along the direction of that component. Work equals the change in energy of an object or system. We always specify what we are doing work ON.
Notice the word, “moving.” Holding a 10-pound sack does not result in your doing work ON the sack. Gravity is also doing no work on the sack. No work means no energy change for the sack, and to address Wilhelm’s challenge, no energy “expenditure” by the earth. When the sack falls, the earth’s gravity does work on the sack, since it moves toward the ground. The earth moves imperceptively upward at the same time, as Newton’s Third Law predicts.
Energy is defined as the capacity to do work, not as the capacity to exert a force, as Wilhelm suggests. Forces, in fact, change the energy of objects and systems, not the other way around. Otherwise, we would have to scrap both Newton’s laws (which work really, really well 99% of the time) and the laws of energy, work and thermodynamics. I’ll let WIlhelm work out those details and eat my hat if he later wins a Nobel prize in physics.
Einstein, for his part, succeeded in turning Newtonian physics on its ear. His conception of gravity resulted from his earlier work with the effects of motion on time, space and matter. If you could travel at near-light speed, your observations of the world around you would be distorted. It would appear, for example, that external objects were curving around you as you approached them.
Special relativity dealt with constant velocities. General relativity dealt with non-constant velocities, accelerations, and gravitation. Einstein proposed that the attraction of two objects toward each other results not from a force they exchange but from the curvature of the space in which they exist.
The Sun, for example, with its 1030 kilograms of mass warps the space around it quite a bit. The planets are moving inertially through that space, as Newton’s First Law dictates, but the space is curved. So we see the planets follow elliptical paths. Light, meanwhile, must also curve as its passes by the Sun, since it has to travel through that same space. Einstein’s 1916 calculation of the deviation of starlight grazing the sun and its verification in 1919 during a solar eclipse propelled the fluffy-haired scientist into worldwide fame. As strange as it seems, space has shape, and objects move according to that shape, much as a ball rolls down a hill.
Now I think dot has picked up on some of these ideas, and perhaps Wilhelm too in his denialist fashion, but neither “gets” the big picture. A person with just a hazy sense of physical concepts cannot develop singlehandedly an entirely new model of physics. After 400 years of effort by countless men and women, physics as a science is pretty well undeniable. Gravity, specifically, is here to stay, folks, no matter how hard you try to forget it.
The Ultimate Hitchhiker’s Guide to the Galaxy
July 29th, 2006 at 10:17 am
I was a physics undergrad, then ended up with a BS in chemistry and now a PhD. I postdoc’d in condensed matter physics.
That said, I confess that there are parts of physics that I can do, but don’t understand at a visceral level (which sounds vague, but I’ll explain). I’m not talking about quantum mechanics- I’m pretty sure I’m in good company not really understanding that.
Rotations of rigid bodies always leave me in awe. Gyroscopic motion- I have derived the equations a couple of times over the years, I can predict what will happen, generally- but it still looks like magic to me when someone rotates a spinning wheel while sitting on a bar stool, and they rotate. Where the torque comes from, really- while it is knowable, I wonder if it is, if the term makes sense, intuitable? Without the discipline that science imposes, that we defer to derivation and experiment, most people are left with accepting or rejecting a proposition based on gut feelings, which stink as truth detectors.
Science is hard, and even with plenty of training and experience, doesn’t necessarily come naturally. Yet it is the one intellectual creation of humankind that can help us solve so many human problems (to be sure, it can help create them, but there is a pointed lack of symmetry- causing trouble almost never requires science). So it is awful that people get through school knowing none of it. They are done a great disservice by not being exposed to science early, often and with feeling. I appreciate what you do as a science teacher. I would not have pursued science without the help of dedicated people like you.
I lament your experience with the germ deniers. This idea has meant more to the welfare of more people than almost any other scientific idea. I did read that Pasteur was a little fast and loose with some data, and this certainly impugns his character a bit if it turns out to be true, but science doesn’t depend on personalities.
The GTOD has been borne out by experiment and experience. Quacks still come out strongly against it, and there is something really peculiar in human nature that wants to believe the lone voice against a sea of evidence.
A couple of generations back, relatives of both my wife and me died from water-borne illness. My own parents were saved (from peritonitis and tuberculosis) with antibiotics. So it irritates me to see the GTOD being pooh-poohed, to the point that I would be hard-pressed to be as gracious as you were in a discussion.
July 30th, 2006 at 12:34 pm
Wheatdogg, Thanks for the inclusion in this epic saga. I credit most of my (limited) knowledge of physics to Discover and Scietific American. My parents got me subscriptions to them from high school through part of grad school. A pity that more parents don’t put that kind of interest in their kids learning. Physics didn’t get much mention in my high school, outside of the introductory section in freshman chemistry or as a senior year elective. Just enough to get by on, or enough to have fun with for the ones who were passionate about it.
A few of my friends went on to get doctorates or masters in physics, and when we get together, I play these games with them. Funny how disturbed it makes them. Especially when I tell them that they are liars because nobody can see the particles they are talking about. I guess one person’s fun is another person’s odd delusion.
July 30th, 2006 at 7:21 pm
The problem is not so much that these people never had science in high school, but that it was probably taught poorly. As a high school science teacher, this problem is one I face every time I meet a class. We have to teach content (formulas, methods, etc), but we also should teach critical thinking, the philosophy of science, the procedure of science (not the sci. method), and what makes science, science. Too many “deniers” throw around terminology as if they understand what the terms mean.
And yeah, science is hard, but so is learning to play Beethoven. Learning science or piano has to be done one step at a time. Teenagers get frustrated when they want me to explain relativity or quantum physics but I tell them to wait a few months until we cover the basics. It’s an incremental process, and pretty time consuming. I’ve been studying physics for 30 years or so, and I still don’t fully understand some aspects.
July 30th, 2006 at 11:38 pm
I recall hating ’science’ class in middle school, though I was already a science geek and thus was not deterred by this. But in class, it was memorization of terms in ‘biology’ or even worse, ‘earth science’. They were abyssmal. They captured nothing of the fun of figuring stuff out. So it seems to me that one who teaches science at the high school level might have to deconstruct what it is that kids mistakenly think science to be before getting to the good stuff.
I have never taught more than as an adjunct and as a grad student, so my experience is limited. When I taught chemistry, I told kids that my own approach was to get a good, useful cartoon model of what was going on in my head- one that no doubt glossed over a lot, but still was accurate enough to use reason through problems. This wasn’t a substitute for ultimately getting in to the bloodshed of theory and calculation, but if the model is good, it can act as a sanity check against mindless application of formulas. Chemists, in my experience, often reason no other way.
Echoing what you said about what needs teaching along with the science: when I taught college freshman chemistry, I recall thinking that the details that I taught students were probably going to have a half-life of a few months, whereas what they really needed was to learn about how and why science works, why evidence matters, and how easy it is to be fooled. Have you seen Theodore Schick’s little book “How to think about Weird Things”? It might be a bit much for high schoolers, though I think the outliers would love it. But it is chock full of excellent case studies of critical thinking, applying a handful of criteria that Schick develops.
July 31st, 2006 at 10:34 am
Wheatdogg, I also thank you for this bit of re-education. However, I think you may not have addressed the heart of Dot and Wilhelm’s misunderstandings, or perhaps have not phrased it in a way that “clicks” for me. I say that because I partially share their misunderstanding (though not their conclusion!) I suffer from the phenomenon you describe of my physics education jumbling itself in my memory…
I can best explain myself this way: Some time ago, I read online a debunking of a “free energy” machine, and though I’m having difficulty finding the original article, this is the machine:
http://www.lutec.com.au/how.htm
The machine is based on a very similar misunderstanding to Wilhelm and Dot’s. As explained in the above link, the device’s creators observed that an electromagnet consumes electricity to hold an object against gravity, while a permanent magnet does not. Therefore (they conclude), the permanent magnet must also be expending some sort of energy. To avoid violating thermodynamics, they conclude this energy is some property of magnets at an atomic or subatomic level, and is gradually somehow degraded or “used up” over time…but that magnets store massive reserves of this energy.
I had no doubts the claims were false, and that there were good physical explanations as to why, but I still don’t entirely understand the error in their original observation, though I think I have some vague idea. Regardless, I could use some more elaboration as to why an electromagnet/my arm expend energy to hold an object against gravity, when obviously no work is being done on the object.
July 31st, 2006 at 9:09 pm
Well, I’ll give it a shot. First, the electromagnet actually does not “consume electricity.” If you wrap some wire around a steel nail and connect the ends of the wire to a battery, you will have a weak, but cheap electromagnet. There is energy “loss,” however, because running current through a wire invariably heats up the wire, the battery and the iron core. The electrical current stays in the circuit.
The magnetic properties of the iron core are latent. Each iron atom is a tiny bar magnet, with a N and S pole, resulting from the electron motion in it. (Moving electrons = electric current) The magnetic field created by the current in the wire forces the iron atoms to line up with the wire’s magnetic field, thereby reinforcing the wire’s field.
The wire’s field, BTW, exists with or without the iron core. Electric currents and electric fields are always accompanied by magnetic fields.
Now a bar magnet is not actually permanently magnetized. It is a magnet because its atoms are aligned N to S. Given enough time, any magnet will lose its magnetic field strength because random atomic motion will eventually knock iron atoms out of alignment. You can accelerate the process by heating the bar magnet (red hot iron will lose its magnetism, loosely speaking), dropping the magnet, beating on it with a hammer or leaving it unpaired with a similarly sized magnet to close the N to S magnetic loop. (U-magnets and horsehoe come with metal keepers that bridge the ends of the magnet for this reason.) Maintaining a magnetic field in air, which does not support a magnetic field very well, will accelerate the randomization of the atoms’ alignments.
The ultimate source of the energy creating those atomic magnetic fields is the motion of the electrons. Here we get into quantum mechanics and leave classical energy theory. You might conclude, as some physicists might have before the quantum mechanical model of the atom, that the “effort” of the electrons’ setting up a magnetic field around each atom would result in their losing kinetic energy and falling down into the nucleus. The QM model, first proposed by Niels Bohr in 1912, instead states that each electron has its own “place” in the atom, below which it rarely if ever dips. So the electrons merrily cruise along, creating magnetic fields, but their group effort does create some thermal randomizing motion. Since there are countless iron atoms and 56 electrons in each one, they can share the load for an awfully long time, giving the impression of permanence.
The Lutec motor sounds like so many similar “free energy” units which share the same basic flaw. Any motion, be it mechanical rotation or electrons in wires, creates heat. Connecting to a load means more heat loss and requires the power unit share some of its energy. You may be able to create a prototype that can spin for days on a 9V transistor battery, but once you expect the contraption to do any work, like propelling a car, that 9V battery will be dead in no time. It’s the first law of thermodynamics, aka the conservation of energy. Inventors that say a unit has an output to input energy ratio of more than 100% are lying. The Lutec site’s equations are just restatements of the definition of electric energy and Ohm’s law and do not support their argument.
Finally, back to the whole work and energy thing. To do work on an object or system requires the object or system move in the direction or against the direction of the force on it. I do work on a sack of groceries when I pick it up or put it down, but I do no work on the sack when I carry it from the car to the kitchen on level ground. I do work on my legs, however, since I have to move them up and down to walk, so I expend energy in moving the sack vertically and on my legs to move my body horizontally. A good bit of that energy turns into heat, too.
Well, that was a long explanation … I hope I addressed at least some of your questions. Ask again if you need clarification.
July 31st, 2006 at 10:46 pm
This basic misunderstanding of physics is fairly widespread. People equate work with force.
Here is a typical newsgroup thread.
http://groups.google.com.au/group/sci.physics.electromag/browse_frm/thread/b5b300f758851418/b89dbd8a52356289?tvc=1&hl=en#b89dbd8a52356289
The Lutec scam is sad. They managed to convince friends and family to give them money. At least no-one appears to have lost their life in contrast to the “rethinkers” that deny the link between HIV and AIDS.
I too was reminded of the Lutec scam. The basic misunderstanding of work and force are identical.
The Australian Skeptics have thoroughly debunked the scheme.
http://www.ratbags.com/rsoles/comment/lutec.htm
It is surprising (or perhaps not) how many HIV “rethinkers” also “rethink” physics or some other part of science. There is a common pattern. Reliance on “common sense”. Antipathy to authority. Discovery of “anomalies” that in reality reveal the profound ignorance of the “rethinker”. And above all an extreme arrogance that allows someone to believe that they (often with little or no training) understand something better than the vast majority of scientists trained in the field. Apparently all physicists blindly and unquestioningly follow the “orthodox dogma” and any heretical ideas (such as free energy) are censored by the authorities.
July 31st, 2006 at 11:04 pm
That’s Wilhelm’s tack in his latest post at Tara’s site. We are all blid sheep believing whatever we learned in frosh physics, whereas Wilhelm has all the answers. Too bad they make no sense.
My dad, an intelligent but not college-trained electronics technician, was once entranced by Joseph Newman’s energy machine, an electric motor that supposedly produced a prodigious amount of horsepower from a single 9V battery. Newman, your typical self-taught inventor, claimed to have reconceptualized EM theory and to have discovered a way to extract more energy from EM interactions than ever before imagined. Dad bought me Newman’s book for a pretty penny, IIRC. It was rambling, confusing and full of diatribes against the establishment.
And his machine just plain did not work. No one could replicate his results, and experts inspecting his prototype marvelled that it ran at all.
There’s another scam floating around purporting to provide “investors” with prototype household generators that will produce electicity for pennies. Strangely, there never seems to be enough money yet to finish production of the first prototypes, so the scammers keep milking “investors” for more money.
Investor here = sucker.
July 31st, 2006 at 11:45 pm
Oh! So the electromagnet would hold the object indefinitely if there was no resistance in the system? Such as superconducting? The muscle analogy made a lot more sense to me, but I couldn’t connect it to the electromagnet.
Thanks for rehashing that!
August 3rd, 2006 at 4:29 pm
Blog Carnivals Roundup 3…
Unfortunately, the next Skeptic’s Circle isn’t yet up at Daylight Atheism, but you can read up on all the latest science post at the Tangled Bank while you’re waiting.
Also, here are my picks:
Dynamics of Cats has a post on biosign…
August 3rd, 2006 at 6:35 pm
This is why researchers using the “wait and see” method of gravity research (jumping off tall buildings and taking data on the way down) has not led to any publications in the refereed journals, although it’s attractive to journalists.
Also relevant:
Understanding Public Complacency About Climate Change
http://web.mit.edu/jsterman/www/StermanSweeney.pdf
Authors’ comments here:
http://www.opendemocracy.net/debates/article-6-129-2455.jsp
Brief quote from the latter page:
“We found a widespread misunderstanding of climate change dynamics. Two-thirds of the subjects believed global temperature responds immediately to slight or dramatic changes in CO2 emissions. Still more believed that reducing emissions near current rates would stabilise the climate, when in fact emissions would continue to exceed removal, increasing greenhouse gas concentrations and radiative forcing.
“Such beliefs make current wait-and-see policies seem entirely logical, but violate basic scientific principles of conservation of matter.”
August 3rd, 2006 at 10:53 pm
Oh! So the electromagnet would hold the object indefinitely if there was no resistance in the system? Such as superconducting?
To an extent yes. The limiting factor is the need to keep the contraption cold enough to superconduct, which requires — guess what? — work. It’s one of those laws of thermodynamics that heat flows from hot to cold. So to keep things cold, we have to “push” the heat “uphill” with some kind of device. Your fridge and AC work that way, using electricity to circulate refrigerant around to pull heat out of the box (or house) and expel it to the outside world.
In the old days, the energy required was different. The ice man drove around town, delivering blocks of ice to put in people’s iceboxes. His labor was the “heat pump.”
August 4th, 2006 at 7:05 pm
Well, I made it over here at last, leaving you a head start (enough rope, that is).
Normally I wouldn’t have brought up gravity on Tara’s blog, but you (wheatdogg) had to throw a challenge around, and you didn’t expect anybody to accept it. So now it’s time for you to face the consequences. Actually, I ambushed you on Tara’s blog, and you didn’t even know from which direction it came.
The first line of defense seems to be, whether it’s from biologists or physicists, “Oh, but you don’t understand anything about the field”. Well, let me surprise you.
The only one on Tara’s blog who clearly understood there is something wrong with the Newton gravitation hypothesis is dot. Wheatdogg, is not a scientist, but a true believer. He believes anything the high priests have told him, no matter how implausible. But it has been 300 years since Newton. And in those three centuries, no physicist except Einstein has had the guts or the brains to point out that Newton’s gravitational “force” made no sense? I mean, have all of you been sitting there for 300 years, playing with yourself? I’m underwhelmed.
I gave an example of a man holding a 10 lb bag with an outstretched arm. If there is a gravitational force, it is not doing any work, because the bag is not moving. But the man expends a lot of (chemical) energy, and his arm gets tired.
So he drops the bag, and it falls down to the ground. Now the gravitational force is performing work, because it moves the object in the direction of the force. Where does it get the energy to perform this work? And when you try to answer this, please note that just claiming I don’t understand any of this is not considered a valid answer.
One excuse might be that a 10 lb bag of groceries is so minute compared to the mass of the earth that the energy expended by the earth cannot be measured.
Fair enough: Let’s consider something heavier: The moon. Without gravity, the moon would just fly by, right? But it’s being held in orbit by the earth. This orbit is at a 90 degree angle to the supposed gravitational force. That means the Work Function is zero. No work is performed then. Compare this to a boy swinging a rock, attached to a string, around. That certainly requires energy.
Yet, this is exactly where the flaw in the theory lies: Comparing a rock on a string with planetary orbitals. The tension in the string is a real force. Gravity is not. Does anybody ever stop to wonder what such a “force” working at a distance means physically? I did, even as a kid. And it doesn’t make any more sense to me now than it did then.
Let’s do a thought experiment. Say, the sun disappears instantly. At that moment, the earth and all the other planets will fly off into space. But we won’t know about it until about 8 minutes later, because the light from the sun takes that long to reach us. Gravitons anyone? Traveling faster than light?
I’m glad somebody mentioned permanent magnets, so I don’t have to bring up the subject. Wheatdogg already stated that the magnetism of permanent magnets can be weakened by dropping the magnet, heating it, or hammering it. Let’s try something more gentle: Hold two magnets close together, with the two North poles (or Southpoles) facing each other. They will repel one another, and it takes force to hold them in place. After some time you will be exhausted, but the magnets will not. You expended energy, the magnets didn’t; where would they get this energy? And you’ll also find that their magnetic fields are not drained.
Now do you still think you understand magnetism?
I’ll leave it at this for today. I have other battles to fight too. With Chris Noble, for example. Because the virus he’s being paid to defend (HIV) is of the same mythical quality as the graviton. Pure science fiction. But I’ll find him somewhere else, so we can stick to physics on this board.
Have a nice weekend, y’all.
August 5th, 2006 at 2:35 pm
Wilhelm-
In your example of the bag, the energy came from the work done against the gravitational field to get the bag to whatever height you got it to. He picked it up, and did work against the field.
A question about your magnet example. Suppose, instead of being held by hand with like poles together, you fixed them in some holder that wouldn’t fatigue. No movement, no work, agreed? Or, do you think that somehow there is some infinite expenditure of work both by the magnet and the brace? Because if you loosen the constraint on the magnet, it will move.
In the case of an arm holding up something against gravity, the work done is work against entropy- the muscle fibers would relax into a less ordered state left alone.
None of this is to suggest that, deep down, there are not existential mysteries at the heart of science, but these questions you raise about gravity suggest that you aren’t thinking clearly. The energy of position that the bag has at 10 ft off the ground came from lifting the bag against gravity. Dropping it returns it.
An arm needs chemical work to hold up the bag against gravity because the free energy of keeping a muscle flexed is positive. A wooden frame wouldn’t get tired.
And ad hominem attacks are unbecoming from someone who fancies himself as having some superior insight into science. Let’s see if your theory fulfills some basics of what philosophers call ‘criteria of adequacy’ - what predictions does your ‘theory’ make that others do not? What gaps does yours paper over?
All us stupid scientists, who can use silly old newtonian physics to get from the earth to mars within a minute or so of predictions have set a pretty high bar, and it won’t be crossed with smartassed remarks or smug self love.
What have you got? Einstein had 43 seconds of arc per century offset in the perihelion of mercury, a tiny but measurable effect. So go for broke- I think us stupid ol’ ‘true-believers’ in science are up to it.
August 5th, 2006 at 8:14 pm
Dave Eaton wrote:
“In your example of the bag, the energy came from the work done against the gravitational field to get the bag to whatever height you got it to. He picked it up, and did work against the field.”
Now why did I expect that somebody would come up with this argument? What you’re saying, Dave, is that the “negative” work from lifting the bag up cancels the positive work done by gravity. Well, it can’t be denied that the gravitational force (if it exists) does work. And that requires expending energy. If that has to be made up by lifting the bag in the first place, then my question is: How does lifting the bag “charge up” the energy source of the earth, to compensate for the energy that is drained from it while the bag is falling?
And, eh… How about things that go bump in the night? Meteorites falling to earth? They don’t need to be lifted up first.
In the case of the two magnets: If you clamp them, they don’t move, so no work is performed. I agree. But if you release the clamp, they will move, as you state.
Where do these permanent magnets get the energy to perform this work? If there really is an energy source, it doesn’t seem to get drained, because you can repeat this experiment endlessly.
You’re right about Newton’s model allowing pretty good predictions in astronomy and space travel. So it is useful. But let’s not forget that it is no more than that. It is based on purely geometrical descriptions of planetary motions, namely Keppler’s laws. And Newton really did not have to do much work to arrive at his equation for gravitational attraction. It was all there already. But having an descriptive equation does not mean it tells us anything about physical reality. We really don’t know what’s going on. Newton postulated the existance of a gravitational force. Upon close scrutiny, this force violates the laws of physics, but the physicists just gloss over it. Good grief! And you believed in it for 300 years?! Gravity force is an artificial concept, just to make the calculations come out right; a fudge factor.
The same can be said about the Strong Nuclear Force. First, physics teaches us that two positive charges repel each other. So a nucleus containing 92 protons should fly apart, right? Well, of course we know it usually doesn’t. But if that nucleus has 143 neutrons instead of 146, it does happen, but only to some of them. Here again, we have to grab a mythical force out of the hat, in order to explain the stability of atomic nuclii. Obviously, there’s something fundamentally wrong with our understanding of atomic structure (the Bohr model). But do physicists lie awake at night, worrying about it? They should, but they don’t. That’s why I call most of them “believers”. They perpetrate science on faith alone. And that smacks of medieval times.
Furthermore, I have my doubts about this remark:
“In the case of an arm holding up something against gravity, the work done is work against entropy- the muscle fibers would relax into a less ordered state left alone.”
Entropy changes are of no consequence here. Even if a resting muscle is in a state of higher entropy (I say IF), only part of the chemical energy spent (use of ATP) is used to lower the entropy. The rest is spent on performing work. If no work can be done, because the muscle is pushing against an immovable object, the energy is converted to heat.
Finally: “ad hominem attacks”?? Against whom? I read my post again several times, but couldn’t find any. Obviously, you’re not used to the real battlefields at other blogs. The ones where I’m dealing with the vermin who have been sitting on a pack of lies for more than 20 years about some virus that’s supposed to cause AIDS. If you really want to see me behaving in a condescending manner, visit one of those fora. Here I’m Mr. Nice Guy.
I may have made a few snide remarks to Wheatdogg, but he had it coming. He calls me a “germ theory denier” (which I’m not), and suggested at another blog that I might not have taken a physics course in college. Which is a ridiculous suggestion. Bud ad hominem attacks? You haven’t seen anything yet.
August 5th, 2006 at 11:15 pm
Wilhelm-
A couple of points-
A single ad hominem is enough to prove the point. “True Believer” wasn’t a compliment, I’m guessing.
As far as my not having seen anything yet, spare me. It does your arguments no good. They rise or fall on one point, and that is conformance to reality as revealed by experimental data. As for what’s “really” going on, that sort of question is outside science, as I see it. At some level, everything gets mysterious. That was my point about perihelion of Mercury- Einstein’s theory predicted something that could be measured. His theory may be wrong to the core, just like you think Newton’s is, but it works. It describes far more than it explains, though.
That’s what I meant by criteria of adequacy. So, perhaps you have no alternative theory to the Newtonian/Einsteinian/string theory to explain gravity, and perhaps you do. There may be little philosophical comfort in ‘merely’ describing phenomena. But that is at some level all science will ever do. Then other, more complex explanations build upon those.
My point about entropy was an allusion to Gibbs free energy; entropy is best seen as a force in its own right, at least a driving force, driving things like mixing, expansion, etc. If you doubt this, consider relaxing a taut rubber band- the restoring force is often ascribed to the elongated bond energy, but statistical mechanics shows otherwise; it is an entropic effect. Thinking about the muscle against an immovable object- the entropic term in free energy is temperature times the change in entropy. If you really doubt that a muscle at rest is in a higher entropic state, consider that you would have to expend energy to relax a muscle if this were not the case. By your own reckoning, no work is being done (well, no mechanical work. Chemical work is clearly being done. Against entropy.)
August 6th, 2006 at 10:39 am
Wilhelm –
You write as if I should be reeling from the subtle power of your intellect, as you attack the foundations of my “true belief.” Instead, your compelling ignorance of even basic physics — given that you have a PhD — leaves me dumbfounded. For example, this gem:
Earth’s “pull” on the moon is definitely NOT the same as the boy swinging a rock on a string. For, in order to make the rock move at all, the boy has to exert a torque on the rock by rotating his wrist. If he keeps his hand and wrist stationary, the rock will eventually lose speed and hang straight down. By increasing the rock’s speed, the boy does in fact do work on it. (Or to put it another way, there is a component of the string’s force tangent to the rock’s “orbit” doing work on the rock.)
The Earth, however, does not have to wiggle back and forth to exert its force on the Moon. Although the Moon follows an elliptical orbit (not circular, as you imply), the force Fis always colinear with the displacement vector r, so the torque (Frcos theta )is always zero. If torque is zero, so is the change in angular momentum with time. The total mechanical energy (PE + KE) of the Moon remains the same, which means no work is being done by the Earth on the Moon.
So your comparison of the Earth with the boy does not support your argument, since the two situations are entirely different. You are correct, however, in raising the troublesome aspects of “action at a distance.” Newton himself was bothered by the mysterious “communication” of the gravitational force across space, but wisely chose not to waste time analyzing the question while preparing the Principia. Einstein, of course, explained that spacetime itself was communicating the “force.”
Here’s another gem of minheer’s:
Well, in fact, it would take 8 minutes for Earth’s motion to respond to the sudden disappearance of the sun. Gravity (and gravitons, presumably) travel at the speed of light. To be consistent with relativity theory, it can have no other value. Gravity waves, which GR predicts should exist, also travel at the speed of light. The disappearance of the sun would create a ripple in local spacetime that would reach each of the planets in succession, starting with Mercury. Spacetime would flatten from the center out. Someone pretending to know so much about gravity should at least know this basic fact.
In your own words,
You have surprised me, Wilhelm. You want to tear down centuries of work in physics and attempt to point out its many fallacies, but you plainly do not understand physics well enough to develop a convincing argument. You cannot hope to dissuade me or any other physicist that you are correct, or even worth listening to, if you cannot demonstrate some comprehension of the subject. As I say in my post, dot’s on the short bus of physics. You’re still at the bus stop. Do your homework and come back when it’s completed.
August 7th, 2006 at 4:16 pm
Wheatdogg, would this be a fair explanation regarding magnets and how they can exert a force… Magnets are inherantly ordered, and energy was input at some point to produce this order, ie, align the iron atoms in order to produce a magnetic field. The weak force of magnetism is the result and effect of this order, and the eventual move to entropy is observed as the alignment is lost and the magnet’s strength is weakened. This move to entropy is hastened by actions that cause the order to be lost, including heat, jarring forces, and exposure to randomly changing magnetic fields.
August 7th, 2006 at 4:46 pm
What is the use of blaming each other in such bossy ways? Nothing good will come out of it, such discussions proof to be neverending. The reason therefore is rather simple: Neither side is always right nor wrong - why? Because of the erroneous underlying principle of both science and pseudoscience (without judging who is on which side).
We should always be aware that both sides are speaking of models of reality, not of reality itself, and the inherent nature of a model is that it only has a limited capacity of describing something. We do not have the possibilities to get in direct touch with reality itself, we rely on an indirect access through our limited senses. Even sensors, how sensitive they may be, are nothing more than extensions to our senses.
In many cases an additional philosophical understanding of reality (at least a try to do so) can help to compensate big disagreements that would otherwise lead to serious conflicts. The philosophical approach would help us to develop a more humble view of nature and how it works. Remember that many of epoch making scientists (like Heisenberg etc.) also had a solid philosophical education, making it possible for them to keep themselves “grounded”. I consider this a very important point, because aquiring knowledge, especially “realized” knowledge, depends heavily on intuition, and intuition can only flourish in a certain humble state of mind. Such a fundament is also able to prevent science from being misused, which is a very big problem today.
“Divide et impera” is the real motto in todays science world, especially in physics, and we can see the fatal consequences thereof everywhere.
So to get even more philosophical - the reason, why some weight is willing to fall down, is also based on this “divide” principle - it strives for a more less energetic state, because it is separated from this less energetic state, it is “stressed” by such a state. Of course we all know this to be a fundamental principle in physics, but the underlying ultimate cause is separation. You can go much deeper with this idea, and one conclusion would be, that the so called big bang was the original force that brought this separation of the original state of matter on the way, and all accumulations of matter are consequently striving back to this original state.
Sorry for deviating from the topic
August 7th, 2006 at 8:30 pm
Wheatdogg,
You have explained this point very clearly:
Earth’s “pull” on the moon is definitely NOT the same as the boy swinging a rock on a string.
But that’s exactly the same point I was making! Both situations are not equivalent. Yet, Newton made it appear as if they were.
Apart from Keppler’s three laws, which described the planetary orbits in a purely geometric manner, there is another equation, completely based uopon astronomic data:
v^2 R = K or: v^2 = K/R
This equation says that the distance of a planet to the sun, multiplied by the square of its velocity always equals a constant K, which turns out to have a value of 1.325 x 10^20 m^3/s^2. For the moon orbiting the earth, K = 3.7 x 10^14.
Note that this equation was known long before Newton.
Now look what Newton did:
He took the equation for the boy swinging a rock by a string: F = mv^2/R
where F is the centripetal force, and R is the length of the string. Now substitute v^2 from the older geometrical equation into that of the rock/string equation, and we get: F = mK/R^2.
Hey, we suddenly have created a centripetal (gravitational) force! Needs a little work, still. So we replace the constant K by the mass of the orbied body (the sun or the arth), and hocus, pocus…
F = m1m2/R^2 instead of a rabbit out of a hat, we have conjured up Newton’s general theory of gravitainal attraction! Neat trick, eh?
Does it give a reasonal description of physical phenomena? Yes! Does it conform to any physical reality? No! As I said before, F, the gravitational force, is just a fudge factor. Actually, Newton gave us nothing we didn’t have before, namely Keppler’s laws plus the orbit equation v^2 R = K. And that combination also described planetary orbitals well. No need to postulate a non-existing gravitational force, to get the same results.
Actually, Wheatdogg, you invalidated Newton’s equation yourself when you made the statement I quoted at the beginning of this post.
Yet, several centuries of work by physicists (I’m not impressed) have just glossed over this example of wrong thinking. I’ve worked in a physics lab at a solid university (in the U.S.) It’s amazing to see what strange ideas even famous physicists come up with. But I must say, they are nice people. When I criticize them, they never say I’m right, of course. But they start thinking, and after a while I notice that my words didn’t fall on deaf ears.
The biomedical people are different. They will keep on defending their erroneous theories in a vicious way. And, while physicists, even if they’re wrong, don’t harm anyone, the biomedical thugs, with their nutty virus theories, make lots of victims. Many innocent people have died as a result of the invalid HIV/AIDS theory, for example.
What else is there to say? Oh, Dave: When I said “You haven’t seen anything yet”, I didn’t mean I plan to get nasty on this board. I meant: Go to the boards such as TalkaboutHealth, or Aetiology. There you’ll see some really vicious insults that are hurled back and forth.
As to the entropy issue: Sure there’s a TS term in the Gibbs free energy. But…
Equating an elastic band with a muscle is not correct either.
Finally, Wheatdogg: I hope you will finally start doing your homework too, for a change.
August 7th, 2006 at 10:00 pm
Gopal –
Quite right, which why I suspect Wilhelm and the rest of us will be typing at each other until our fingertips are sore. Newton’s law of gravitation is part of the Standard Model of Particles and Interactions, which is a broader construct laid on top of reality. Einstein’s relativistic model of gravity, which works better than Newton’s under extreme conditions, is yet another model. We use these models to find order in the universe, to help our understanding of it, and to enable us to predict outcomes of physical events. That last is the key to any successful scientific model. My argument with Wilhelm may seem like a matter of semantics, but in fact I am trying to argue that the model we use now works extremely well. There are unanswered questions, to be sure, but that does not mean we throw out what we have.
Wilhelm repeatedly returns to the same question, from where does the earth get the energy to exert gravitational forces? Since he cannot answer the question, he concludes that gravity as force does not exist. Yet objects fall, and the moon orbits the earth. Something has to make that happen. Newton said there was a mutual force acting across space attracting two objects together. Einstein said a massive object warps the spacetime around it, and other objects have to follow the shape of space. Both models work, although Newton never attempted to explain how gravity is communicated across space and Einstein never attempted to explain the origin of mass and inertia.
Now back to you, Wilhelm.
You have deconstructed Newton’s derivation of the gravitational force law, while demeaning his contributions to orbital mechanics. You imply that he “conjured up” some random factors (m1 and m2), yet clearly the masses of the objects must be important to orbital motion. He saw that the Kepler’s laws of planetary motion and Galileo’s laws of kinematics had to be connected in some way.
Copernicus and Kepler had worked out the laws by which the planets orbit the sun. Kepler, for his part, worked out from empirical data all three of his planetary laws. It took him 20 years. Newton was able to mathematically derive all three of Kepler’s laws on a few sheets of paper. Galileo worked out the concepts of inertia, velocity and acceleration. Newton realized that Galileo’s gravitational acceleration had to apply in some way to Kepler’s orbits.
The force that pulled Galileo’s ball down a ramp is the same force that keeps the moon in its orbit around the earth. Newton applied this concept to the orbit of the moon, derived mathematically the trajectory of the moon, and compared his value to the actual behavior of the moon. His calculated value and the empirical value agreed, indicating Newton was on to something.
True, Wilhelm, v^2r = K. But why should K be the same value for all the planets? And how does one determine it for other situations? Kepler did not have the answer. Newton did: K = GM, where G is the universal gravitational constant and M is the mass of the sun. You can apply the same equation, v^2r = GM, to every orbital situation, which is why Newton called it the law of universal gravitation. Newton gave us a theoretical basis for the ancient orbital equation; he explained why it should be true.
[BTW, Wilhelm, you misquoted Newton's "general theory of gravitainal attraction." In fact the law of universal gravitation is
F = G M1 M2/r^2
-- the G makes it an equality and not a proportion.]
Finally,
You missed my point entirely, minheer, or are now twisting my meaning to suit your latest argument. You were using the boy and rock to argue the earth had to pull energy from somewhere to exert a gravitational force. You were saying they were equivalent. I attempted to show this argument by analogy was invalid, since the boy must do work on the rock to keep it spinning, while the earth does not need to do the same for the moon.
Now you claim you know the boy and his spinning rock analogy is in fact not equivalent to gravitation, since you contend gravity is not a “real” force like the tension in the string. Really, you can’t have it both ways. Either the spinning rock is an equivalent situation or it isn’t.
August 7th, 2006 at 10:09 pm
Robster -
Sorry, I forgot to comment on your question. Your argument to me seems valid. Left to themselves, iron atoms would arrange their magnetic fields randomly. It takes energy to align them — increasing the magnetic field intensity and the magnetic energy density. Over long periods of time, this order slowly disintegrates.
As an aside, MRI scans work on this principle. Strong magnetic fields act on the hydrogen atoms in our bodies, increasing their energies. The atoms lose the energy by emitting radio waves, which the MRI machine converts into images of the soft tissues of our bodies.
August 7th, 2006 at 11:07 pm
Wilhelm — I checked back at Aetiology to see what was going on in the thread that inspired this one. I see you intend to divulge an alternative theory of gravity here. So, do you intend do reveal it to us soon?
Actually, I assumed without knowing much of your background that a biochemist must have taken at least freshman physics, and certainly p-chem. I did find an abstract of that paper, too. If you were in the physics department at UVa, did you teach physics, and whose model of gravity did you use?
And I see you also question subatomic theories as well, including the two nuclear forces. Your alternative theories of physics had better be damned good, because you’re challenging some Nobel Prize-winning work here.
August 8th, 2006 at 2:17 pm
Ciphering more on this idea of magnetism being batted around-
The unpaired spin in an atom wants to line up with the others (chemists refer to this as the tendency towards maximum multiplicity) unless there are lower energy states available that forces pairing. Classically, all the spins want to pair.
The situation in a solid is a bit different, though you can still think of the electrons living in states like orbitals. In iron, cobalt, nickel and some rare earths there isn’t really a state of the right energy to force pairing, hence these guys can be magnets. It is a subtle balance of the tendency to want antialign, and pauli exchange energy. But while they align locally, there is some activation barrier against total alignment (the metals in bulk are made up of domains, or crystallites, I think). Enough energy will get them over the hump, and they are then aligned, and thus magnetic.
But the magnetic state is only a local minimum in energy, yet persists, save for entropic action, so magnets won’t run down, generally, for millions of years. If you heat one above the curie pt, though, the material goes back to having only short range order. Despite the exchange energy, there is still a (classical? I dunno) tendency for domains to antialign and not be magnetic.
The really cool thing about magnetism is that it is both a macroscopic manifestation of a quantum effect (i.e. exchange energy is not predicted classically) and a relativistic effect (the magnetic field arises from moving charge because the Lorenz transform rather than Gallilean is necessary to satisfy the principle of relativity).
I am a rationalist to the bone, and yet I still find magnets magical, but not the ‘Harry Potter’ kind of magical. The ‘gee, heres an effect my mind is not equipped to grasp easily’ kind.
And I realize a muscle is not a rubber band. Long polymer chains of various stripes share some characteristics and are governed by similar stat mech is all I meant. The TdeltaS term is important as an energy one has to do work against; left alone, both a stretched rubber band and a muscle fiber will relax. In contradistinction to an iron frame from which one would could hang the 10 lb bag in your choice of gravitational field.
August 8th, 2006 at 8:24 pm
Wheatdogg,
It’s too late at night to give an elaborate answer, but there’s one point I want to correct right now:
“But why should K be the same value for all the planets?”
But it is indeed. However, K is NOT the same for different orbital systems. I gave two different values: One for the planets orbiting the sun, and one for the moon orbiting the earth. You are right, of course, about the correct formulation of Newton’s law. The factor G is actually just a proportionality factor. It never ceases to amaze me that it is regarded as a fundamental physical constant.
(to be continued tomorrow).
August 8th, 2006 at 9:42 pm
When the ancient astronomers derived the v^2r = K equation, they had only two orbital systems to study, and no understanding of WHY the value of K should be unique to each system.
Newton showed that K is proportional to the mass of the parent body (Sun, Earth, Jupiter, epsilon Eridani, …), thereby providing the underlying reason for the variation.
Whether G is a fundamental or a derived constant is a debateable point, I admit. Using Einstein’s formulation gives a slightly higher value of G near very massive bodies, in fact. Nevertheless, to make the gravitation law an equation requires some constant of proportionality.
And why the heck are all our comments now in italics? I suppose I have to find out (grumble, grumble).
August 8th, 2006 at 10:11 pm
Somehow I left an extra italics-begin tag in my reply to gopal’s comment. It stayed in the code and italicized all later comments. I had to copy the offending post into a text editor and paste it back into the WordPress edit window. The built in HTML editor wouldn’t open an edit window.
August 9th, 2006 at 8:59 am
Wheatdogg,
Good morning. I’d like to get back to our main point of contention. You wrote:
“You missed my point entirely, minheer, or are now twisting my meaning to suit your latest argument. You were using the boy and rock to argue the earth had to pull energy from somewhere to exert a gravitational force. You were saying they were equivalent.”
No, I did no such thing, nor did I intend to. I didn’t use the boy and rock to argue my point of view; I only said Newton used it. And IF this model were valid, THEN the earth had to pull energy from somewhere.
As we have seen, the step from v^2r = K to F = G m1 m2 / r^2 is simple and straightforward, IF we are ready to assume the equivalence of planetary orbits and the boy swinging the rock. As you pointed out, both systems are NOT equivalent. But the gravitational force is created by Newtons derivation of his equation from an invalid model (the boy and the rock). So it seems that we are in agreement on the point I first made on Aetiology: “There IS no gravitational force, and Newton had it wrong”.
But Sir Isaac apparently had a first-class press agent, so his model lasted for centuries. Of course it helps that it works well in space travel. Nevertheless, it is based on a wrong assumption. Einstein was the only one who came up with criticism, and launched his own model. That is indeed more accurate, but rather abstract. And it is also merely descriptive, and doesn’t invite physical understanding. How do you explain it to your 5-year old son (if you have one), when he asks: “Daddy, why do things always fall down?” Suggestion: Try 10-dimensional string theory .
In highschool we also had classes in classical mechanics, apart from the regular physics classes. I remember being puzzled by the nature of gravity, even at that early age. But when I was taught that, if an object is quietly resting on a shelf, there is suddenly an opposing force balancing out the gravity force, I felt we were being cheated. Reaction forces such as the Coriolis force, I could still fathom. But this mysterious force, exerted by the shelf, to counterbalance the gravitational force, was a little too much. Of course I pretended to believe pro forma. After all, there were final exams to pass.
Many years later, in the lab of the late professor Jesse Beams at UVa, I worked with magnetically suspended rotors in analytical centrifuges. Those magnetic fields used up plenty of energy. But what did Mother Earth do to compensate?
You asked what alternative theory I had. Well, none of my own, really (I’m a biochemist). But there is one by Mark McCutcheon that appeals a lot more to me than Newton’s or even Einstein’s. As I already indicated, I question the subatomic forces too; they were also postulated to explain the unexplainable. So why not start with the fundamental building blocks of matter itself? Why not replace the Bohr model,which was based on an analogy with the planetary systems, with one where all atoms are continuously expanding? That means we are expanding ourselves, along with our environment, so we would not observe the phenomenon. The earth, being huge compared to ourselves and the objects around us, would expand then with an acceleration of 9.8 m/s^2. If you step out of an airplane then, without a parachute, the expanding earth would come at ya at that acceleration, instead of you falling to earth. In the final result: What’s the difference? I already gave the example of someone hanging from the ceiling of an elevator in upward motion. When he lets loose, does he fall to the floor, or is the elevator floor meeting him?
The expansion theory can explain many things, and does not create the same paradoxes of the classic gravity theory. Is expansion theory the definitive answer? We don’t know yet. But it’s time the most brilliant minds in physics start thinking seriously about it, insteadof clinging to a theory that has so many flaws. Granted again, Newton’s model works reasonably well in practice. But even the phlogiston theory of chemical oxidation works to some extent, if you equate the mythical phlogiston with electrons. Drawing electrons out of a metal or a chemical compound is indeed oxidation.
I think I stepped up to the original challenge: “Who would deny gravity”? Why I should be treated like the village idiot, I wouldn’t know. I often disagree. Whenever there is a consensus on anything, it’s usually incorrect.
The worst offenders are in the biomedical field. But that’s where some serious money is to be made by promoting horror tales that make many (often fatal) victims. I don’t deny the germ theory per se, but I’ll always scoff at AIDS, SARS, Bird Flu, West Nile, Ebola, and other scams.
August 9th, 2006 at 11:08 am
Wheatdogg - You asked:
“If you were in the physics department at UVa, did you teach physics, and whose model of gravity did you use?”
I didn’t have to teach physics. Most of the fundamentals are college material anyway. I only dealt with graduate students there. I headed up a research project using the magnetic centrifuge. There was a controversy concerning the particle weight of TYMV, a plant virus. These viruses are too big to be analyzed by equilibrium sedimentation in a mechanical ultracentrifuge, because the required speeds are too low, causing wobble in the rotor. But it could, theoretically, be done with the magnetically suspended rotor. When I arrived there, I noticed that the longer the centrifuge run lasted, the higher values were found for the particle weight. I didn’t (as most biochemists would) blame the virus, but an artifact. My calculations showed that the loss in rotational speed (even though we had an excellent vacuum) was causing the problem. Dr. Beams, who was a genius at devising experimental contraptions, but didn’t think much of theoretical babble (Oh well, neither did Faraday), told me I was talking through my hat. But shortly afterwards, a graduate student got the assignment of developing a constant-speed system. That did the trick, and our results were published at Proc.Natl.Acad.Sci. 71, 3866 (1974).
Maybe it’s interesting to note that Dr. Beams had an ingenious set-up with magnetically suspended steel balls to measure “Big G”, the gravitational constant, to more decimal places than anyone would care to know. I never knew why anybody would want to do that.
As far as the subatomic models are concerned: It’s such a mish-mash, I don’t know what to make of it anymore. And I think no one does. But whoever has the best press agent gets the Nobel prize, I guess. David Baltimore is also a Nobel laureate; yet I don’t give two cents for his ideas. I see him as a con man.
The atomic Bohr model is flawed, as we all know. This type of structure should emit electromagnetic radiation. Unless, of course, some authority decrees that it should NOT radiate. Diving into quantum mechanics helped putting my mind more or less at ease. At least it gives consistent results. But why? What are we to visualise? Quantum mechanics teaches us that a particle in a box has a finite probability to be found outside the box, in spite of an infinite energy barrier.
Do we really understand anything about nature?
Dave - I can find myself in your comments about magnetism. And I am also awed by the magic. Electro-magnetism isn’t hard to understand, but permanent magnets that exert a force without being drained… A mystery. And nobody seems to care.
Gopal - I agree totally with your remarks from two days ago.
August 9th, 2006 at 11:56 am
Wilhelm, and Wheatdogg-
Has there been any progress in measuring proton decay? I recall this being a hot topic once, but honestly, I have never understood anything about particle physics. But maybe, Wilhelm, people do care, if only obliquely, since the decay of all matter would be kind of an upper limit on the force being applied.
My own interests were/are in organic semiconductors and superconductors. It’s an area of physics where a chemist can make a contribution long before actually understanding the physics, by making new compounds.
One theme here, I think I perceive, is the dichotomy between ‘this is how things seem to be’ and ‘why should things be so’. My understanding of physics is very much as a consumer of the output of theoreticians- how should my molecular magnet act under pressure, does it do so, and is the model offered a good approximation to the observed behavior. In that context, I might hope to understand a limited ‘why’ one compound is better than another. I have, in my adult life, set aside the harder ‘why’ questions as subjects for serious study- there just isn’t time, or hope, with my mathematical limitations, of making a contribution to the bleeding edge. With respect to all involved, I fear that I lack the ability to order various contributing energetic factors involved in deep phenomena like gravity or magnetism, and thus have neither the intuition that I can rely on in (for instance) solid state physics and chemistry, nor the mathematical chops necessary to determine whether or not someone like Roger Penrose or Edward Witten is a prophet or a knave.
August 11th, 2006 at 5:05 pm
Dave, Wheatdogg and Gopal,
Although I’m not a theoretical physicist, I answered the challenge “Who would deny gravity”, because I think it’s important that people start thinking again, even about things that have been taken for granted for a long time. As a little inquisitive kid (who drove his father nuts), I remember being fascinated by unexplanable phenomena such as gravity and permanent magnets. That was long before I ever took a physics course. And years later, when I did, the explanations given did not satisfy me.
My impression is that the physicists are coming up with one extremely complicated theory after another, on various subjects, for the past decades. And we still don’t know whether they bear any relationship to the real world as we experience it, or if they are pure mathematical masturbation. But there is also something like scientific instinct. Some things are just not plausible.
But even wild ideas can be substantiated, if the right kind of experiments are devised. Christiaan Huygens’ wave theory of light must have floored some of his contemporaries. Yet, ample proof was found. I wouldn’t know how to set up an experiment to provide evidence for string theory, but if it is to be taken seriously, the experts in experimental physics better get on the ball.
Anyhow, if I succeeded in stimulating debate, I reached my goal. If I offended anybody, I apologize. But this environment is extremely peaceful compared to the bitter bickering in the biomedical field, where I am usually to be found.
August 13th, 2006 at 5:42 pm
I’ve been away for a bit, since my school year is winding up to start Wednesday. I feel I need to address a lot of you all have discussed here, but at the moment I can’t give much time to the effort. I do have a couple of quick comments, though.
Wilhelm — I would like to see a citation regarding Newton equating gravitation to a rock on a string.
Regarding these statements:
The coriolis force is not a real force. It is an effect of being on a rotating platform, like the earth. The mysterious force exerted by the shelf is the electromagnetic repulsion between surface molecules on the shelf and the objects sitting on the shelf.
Also, I believe you are confusing the Rutherford and the Bohr models. Rutherford’s model and the classical wave model of light predicted atoms would continually radiate EM waves from the accelerating electrons. Bohr’s model presumed that electrons have a certain energy level below which they cannot fall, thus evading the EM radiation problem. Bohr’s model, which later was refined by Bohr and others, predicted that electrons absorb and emit EM radiation only when switching orbits/energy levels.
This expanding earth concept leaves me cold. It presumes that somehow the earth expands according to the object that’s falling. Sounds very Aristotelian to me. Besides, if the earth expands up to meet you, does it return to its original shape when you hit bottom?
Dave –
The last I heard, the proton decay experiments were still waiting for a p+ to decay.
I liked your comment about magnetism — you reveal you know more about it than I do!
And can we please agree that energy is NOT the capacity to exert a force? The operational definition is that energy is the capacity to do work.
Further, we also need to agree, as Wilhelm says, that ultimately we do not really understand all of nature. For some phenomena, we can only describe what is going on. Newton basically did just that, as he never discussed the actual mechanism of how gravity was communicated between objects. Even Einstein’s model begs the question of why objects have mass and why mass should bend spacetime.
August 14th, 2006 at 1:17 am
Godschalk gives Mark McCutcheon as his authority.
He regurgitates material from his book “The Final Theory”.
Some of the reviews on Barnes and Noble are interesting.
http://search.barnesandnoble.com/booksearch/isbnInquiry.asp?isbn=1581126018
“In this book McCutcheon confuses the terms work, energy, power and force in an attempt to draw the reader into his argument that all current physics is based on flawed logic.”
August 14th, 2006 at 6:52 pm
Wheatdogg,
“The mysterious force exerted by the shelf is the electromagnetic repulsion between surface molecules on the shelf and the objects sitting on the shelf.”
Oh - I see. That’s a repulsive force. In contrast to gravitation, which is an attractive force. All by decree? Instead of two mysterious forces opposing each other, isn’t a much simpler explanation for the fact that the object is just sitting on the shelf, that no forces are acting on it at all?
“Rutherford’s model and the classical wave model of light predicted atoms would continually radiate EM waves from the accelerating electrons. Bohr’s model presumed that electrons have a certain energy level below which they cannot fall, thus evading the EM radiation problem.”
That’s more or les what I said. The model (OK, Rutherford’s) predicts constant EM radiation. Until some authority (Bohr in this case) ordered it NOT to radiate.
“Besides, if the earth expands up to meet you, does it return to its original shape when you hit bottom?
No, it doesn’t, according to the Expansion Theory. The earth, as well as all material bodies keep on expanding continuously. As I said, this theory makes more sense to me than gravity and the nuclear forces. We should really think about ways we could test it.
“And can we please agree that energy is NOT the capacity to exert a force? The operational definition is that energy is the capacity to do work.”
Yes, we agree on that. But not on the inverse relationship, which would be that “a force does not need an energy source”. That is obviously wrong. A force DOES require an energy source. And that energy gets drained, whether the force is able to perform work, or just produces heat.
Yes, I think we can all agree that there is still much more insight we need to gain about nature.
August 14th, 2006 at 7:34 pm
Chris Noble wrote:
“Godschalk gives Mark McCutcheon as his authority.
He regurgitates material from his book “The Final Theory”.”
So? This Expansion Theory is not my own, as I already indicated earlier. So I named my source. Don’t you and all other believers in the gravity force regurgitate material from Newton’s book The Principia?
McCutcheon’s book is easy to find; I even saw it advertised by Google on this blog. I can warmly recommend reading the reviews that Chris quoted. What strikes me is that the favorable reviews have been written under the referees’ full names. The unfavorable ones, on the other hand, appear under a pseudonym or even anonimously. These must be rigid orthodox cementheads, who simply don’t want even to consider or think about an alternative theory. Besides, they are too cowardly to spout their venom under their real name.
“In this book McCutcheon confuses the terms work, energy, power and force in an attempt to draw the reader into his argument that all current physics is based on flawed logic.”
That’s exactly what McCutcheon does NOT do. He accuses the orthodox physicists of doing just that, to confuse the unwary into ignoring the unexplainable fact that gravity is a force without an energy source. And he does NOT argue that ALL current physics is based on flawed logic. On the contrary: He argues that a gravitational force would violate the laws of physics.
But, of course, I am used to this kind of argument coming from you, Chris. It’s just like you claiming that I deny the complete germ theory, just because I deny your “funny” AIDSvirus. But we won’t discuss that here. Tara’s blog is a better place for that, or the snakepit.
Amazon has asked me to write a review of McCutcheon’s book too. I’ll certainly do that. And it won’t be anonymous.
August 14th, 2006 at 8:22 pm
Amazon has asked me to write a review of McCutcheon’s book too. I’ll certainly do that. And it won’t be anonymous.
Amazon is quite happy if they can sell more books.
There are indeed a lot of gushing 5 star reviews. The book appeals to a sizable group of people that like to think that they know the truth and all those pompous scientists that spent years learning physics are all stupid and wrong.
The book is typical kook physics. It purports to find flaws in modern physics but does not in fact describe modern physics. He presents an inaccurate strawman version. He purports to offer an alternative theory that is however completely devoid of any detailed mathematical description. He makes frequent appeals to “common sense”. He does not appear to have even attempted to falsify his hypothesis because it contains contradictions that a blind man can see at 50 metres in the dark.
August 14th, 2006 at 9:20 pm
I am perplexed by Wilhelm’s complaint that physicists have “decreed” that there are attractive or repulsive forces, or that orbiting electrons should not radiate EM waves. We are not telling nature what to do. We are trying to explain what nature is doing.
So, Newton in the Principia proposed three laws of motion and the law of universal gravitation. These laws have worked remarkably well for some 300 years, from the subatomic level to the galactic, so most physicists (or civil engineers, for that matter) doubt their efficacy. Within that model (and here is where I will sound like a high school science teacher) we have to address why objects sitting on bookshelves, or students sitting in chairs, do not plummet to the ground, or to the center of the earth. If there is (apparently) an attractive force pulling everything down, for the law of inertia to be valid there must be an opposing force in the opposite direction. Now, it is a well observed fact that books do not pass through shelves, nor students through chairs, so something must be exerting a force on these objects. We propose (within this model) that the opposing force is the electrostatic repulsion between the objects’ constituent molecules. We need these forces to make our model both plausible and self-consistent.
Suppose there is another equally efficacious model, which Wilhelm presumes to be McCutcheon’s, in which there is no need for two opposing forces to cancel each other out, since gravity as a force does not exist. How then can we, within this model, explain why solid objects do not pass through one another? A student can flop into a chair, but the chair’s seat stops his fall to the floor. I have not read McCutcheon’s book, so I do not know whether he explains this observable fact. Perhaps Wilhelm can.
BTW, just because the book is advertised here does not mean I endorse it. I have not quite taken the time to learn how to filter my Google ads.
As for the radiating atoms, the wave model of light emission was fundamentally flawed, as it failed to explain, among other things, why atoms do not continually radiate, why a bright light does not increase the speed of electrons ejected from a photosensitive metal, and why incandescent objects do not radiate an infinite amount of energy in the ultraviolet range. In other words, the predictions of the wave model could not explain observed phenomena. Bohr’s model of the atom, the photon model of light proposed by Einstein, and Max Planck’s reluctant proposal that energy was quantized did provide the explanations.
The test of any scientific model or theory is how well it explains nature, how well it predicts, and how well it holds up to repeated experimental evidence. We don’t “decree” that nature do anything — the Greeks tried that 2500 years ago and it failed as a scientific philosophy. Nature does a pretty good job of doing what it wants to do, despite our fumbling around in the dark for plausible, consistent explanations.
If McCutcheon’s physics, or any other theory can provide plausible, consistent explanations for physical phenomena, and predict future outcomes that can be experimentally verified, then I would fall right in line behind them. This concept that the earth is continually expanding, providing an accelerated reference frame, is not plausible or consistent. All these expanding objects (moon, sun, stars, etc.) have different rates of “expansion”, since they have different gravitational accelerations, implying that some will eventually overtake the others’ expansion. The sun, then, would have caught up to the inner planets long ago, and we would be toast.
So, I am unconvinced and will continue (starting Wednesday in fact) teaching the “party line” in physics.
August 14th, 2006 at 10:28 pm
I am absolutely ignorant of this ‘expansion’ theory, so I’ll go look before spouting, but I would ask a couple of simple questions (criteria of adequacy questions, as it turns out, are a good first step in hypothesis evaluation).
Is there something that the expansion theory explains that regular gravitation does not?
Doesn’t it contradict an observed fact, i.e. that expansion happening at different rates would lead to objects overtaking one another (I see Wheatdogg has a similar question), or is there something I’m missing.
Actually I think that there is a lot to recommend a hardheaded, skeptical view of the ontological basis of a lot of physical theories. Nevertheless, I think that there is almost no compelling reason to endorse off-the-wall (or, more politely, unconventional) theories in their place in the absense of some deficiency in current theory. Not understanding the current theory is not enough- it should demonstrably lead, in its formalism, to some absurd or wrong result, or fail to predict something.
On the other hand, in chemistry we rely on models that we absolutely recognize as rotten, but useful…
August 14th, 2006 at 10:50 pm
Is there something that the expansion theory explains that regular gravitation does not?
The first question is does it explain anything?
It purports to replace not only gravitation but electromagnetism and the strong and weak nuclear forces all with a complete absence of mathematical description.
A complete lack of mathematics of course makes it attractive to a lay audience but also means it is completely devoid of content
August 15th, 2006 at 6:41 pm
Wheatdogg wrote:
“I am perplexed by Wilhelm’s complaint that physicists have “decreed” that there are attractive or repulsi