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Einstein's Biggest Blunder That Wasn't
jose parinas writes "The genius of Albert Einstein, who added a "cosmological constant" to his equation for the expansion of the universe but later retracted it, may be vindicated by new research.
The enigmatic "dark energy" that drives the acceleration of the Universe behaves just like Einstein's famed cosmological constant, according to the Supernova Legacy Survey (SNLS). Their observations reveal that the dark energy behaves like Einstein's cosmological constant to a precision of 10%."
The cosmological constant is an extra term in Einstein's equations of general relativity which physically represents the possibility that there is a density and pressure associated with "empty" space. The inclusion of this vacuum energy term can greatly effect cosmological theories.. html
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http://super.colorado.edu/~michaele/Lambda/lambda
http://en.wikipedia.org/wiki/Cosmological_constan
Will Einstein's genius never cease to amaze us post-humously? Probably not.
This will be a great thing for students to look up if they are doing (or going to do) relativity in school.
Can anyone explain the idea behind dark matter and dark energy ? I mean if it is just a mathematical problem or has some experimental justification as well.
IIRC, Einstein "fudged" his equations (i.e., introduced the cosmological constant) to stop them from predicting that the universe would expand. Subsequently, Hubble discovered that the universe was expanding after all. Still later, it was found that the rate of expansion was not in line with Einstein's un-fudged equations. Since then, the value of the cosmological constant has really depended on what value you measure for the expansion of the universe.
So, why is this news?
If he's so smart how come he's dead?
"I'm going to f***ing bury that guy, I have done it before, and I will do it again. I'm going to f***ing kill Google"
Alright, Einstein's blunder is no longer his "comsmological constant"...
His blunder has merely changed to the premature retraction of his "cosmological constant."
Thank you, Edward Snowden.
"Arguments from authority are worthless." —Carl Sagan
In astronomy (and other fields) you often have to live with large errors. That doesn't mean the science isn't valid. If the errors on your data are 10% and your theory is within the 10% error of your data, then fine, you have not invalidated the theory. On the other hand, if your error is 5% and the discrepancy with the theory is 10%, then you have something to think about.
If it weren't for deadlines, nothing would be late.
Windows is like decaf - it tastes like the real thing, but it won't get you through the day.
The aliens gave him the theory -- including the cosmological constant. Unfortunately, there wasn't actually a justification for it. Thinking quickly, Einstein ad-libbed that it without it, the universe would be expanding, "and, uhh, we all know that's not true, right, fellas?", sacrificing the chance to be the first one to "predict" this. He copied the answer from the back of the book and got busted for not showing all the work. C'mon, who hasn't that happened to?
Scientists did not prove anything. Some merely published a theory. It is not in anyway proven. Science is not like engingeering where it either works or doesn't. The scientific process takes a while, and dark matter and dark energy are still a vital theory in explaining expansion of the universe. So please don't tell me Dark Energy doesn't matter, because if that's true, I'm wasting a lot of my time.
G.W. Bush is alive, what a genius!
You can't handle the truth.
In later years, studies will show that Einstein actually CREATED the universe in some kind of unconcious blunder, giving him the "Genius" over the universal equations we praise today.
What a fraud, and I would assume would be then, a god.
~--~
Do not mind the one with the crazy, for he is sane
dark matter anymore as per this past story.
Granted, it's unproven at this point, but Occam's Razor and all, I vote for the theory that makes sense with matter and energy as-is and doesn't require some exotic matter/energy that exists only as speculation to fill an unknown.
IIRC his biggest blunder was discounting quantum physics and spending the last half of his life trying to come up with an alternative model that didn't require the universe to be probabilistic.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
Consider a spherical mass of uniform density. If an observer stands at the surface, the gravitational vectors sum to a unit vector from surface to center. If the observer stands at the center of the mass, the gravitational vectors sum to zero (all vectors cancel). If the observer stands at any location in between the first and second position, the gravitational vectors can be given as two sums, zero (canceled) for an equidistant radius from the observer's position to the surface and towards the center, and a distance vector from the observer's position and the residual (uncanceled) mass.
The distance vector between the observer and the residual center of mass is constant at any point between the surface and the center of the mass. The residual mass decreases linearly as the observer descends towards the center. The gravitational force on the observer decreases linearly to zero over this domain. The radius of the sphere is the radius of maximum gravitation.
Gravitational force may cause the radius of the sphere to contract. As the radius shrinks, it approaches the center of mass and therefore increases the gravitational force upon an observer standing at the radius as the inverse square of the change in radius until it relativistically approaches a point at which escape velocity equals the speed of light. To an external observer, the radius will seem to shrink more and more slowly until it seems to stop as it approaches this point. Likewise for the internal observer, but neither mass nor energy can now escape from inside the radius to the outside, so we cannot communicate with him unless we shift our perspective to his.
Staying with our external perspective for the moment, however, we can measure the gravitational force at some distance from the radius, and observe how it acts upon other masses. Nearby matter may get swept into this gravity well, adding to the total mass of our system and increasing its externally determinable radius. But by appearing to slow down and stop at a radius greater than that of our original mass, it would not seem to reach the original radius at all.
Now let's depart our external universe and try to figure out what's going on with our inside observer. First of all, he's not seeing any in-falling matter because his frame of reference is also much slower than that of the radius, in fact he'd have to wait infinitely long before anything like that would happen, so let's just say it doesn't. But that doesn't mean that he cannot observe any effects at all.
What our man on the inside discovers is that there is intense energy, in the form of pressure, being applied to his little micro-universe. This pressure continues to build and build, charging our little spherical mass like a battery, until maximum energy density is reached. But the pressure continues, so the mass does what it has to do, it inflates.
Our mass isn't just expanding in space; it is expanding "space." As pressure energy continues to pour in, the inflation continues until certain physical properties of matter and energy begin to assert themselves; and the inflation proceeds outwards and away from the original mass -- into the new universe.
This is one possible explanation of how our universe may have begun. In searching for evidence of such a hypothesis, one might hope to find some sort of inflationary pressure which seems to operate against gravity. Since this "dark energy" seems probably, this may be a feasible cosmology.
Peace and love, y'all
"Affect"... "Can greatly affect"... 'effect' is a different word, with a different usage.
An informative post, and I'll accept moderator punishment for grammar nazi-ism.
"It's overkill, of course. But you can never have too much overkill." - Anonymous Slashdot Coward
Comment removed based on user account deletion
Despite the theoretical blunder of a few (I find it doubtful that anyone would use Newtonian mechanics to calculate cosmological problems anymore), most people are using GR for their calculations, and this is a real effect. There is an acceleration that, if the data on redshift vs. distance is correct, can only be explained within GR by adding a repulsive term to the equations.
Remember, these publications are peer reviewed. If the mistake were that simple, the reviewers should have caught it.
That turns out not to be the case. And I was far from the only poster to point that out. Please read the Slashdot comments for critical analysis, not just the blurbs.
Besides which, dark matter has nothing to do with dark energy.
I hate that problem !
Isn't there a medical solution for these things?
Do astronomers have more of these than the rest of us?
Or do physicists and mathematicians also suffer from it?
Gads, even Einstein had the problem.
Einstein and Hoffa are chillin' on the dark side of the moon.
:)
They're just waiting for someone to come pick them up.
Pretty Pictures!
That's my take on modern cosmology. That there exists this one substance, the vacum substance, the stubstance of space-time itself. It can be imagined as a drop of water, or equally as a cloud of moisture. It contains volumes within it that are "denser" than other volumes. We say that there is "more space" (or less?) within those volumes. All "material" goods are then just some kind of configuration of this "space-time" stuff. I think also that based on quantum mechanics, and the "Beckenstein bound", material within a given volume can be realized in much the same way pictures are made up of "pixels" on a computer screen. Think of it. Your computer screen resolution determines all objects that are "realizable" within its resolution. The Beckenstein bound then formulates a given volume for space-time in which objects of a given size can fit. The relationship of the "density" of space-time then should directly influence the Beckenstein bound such that, if there is "more space", then there should be the possibility of a larger number of possible quantum states within the abstract volume of space-time.
If you had a glass sphere the size of a basketball, what are all the material objects that are realizable within that space? Well, we can put car keys, pens, small animals/insects, etc. But we cannot put a house inside a basketball right? Well maybe a doll house. But how would we go about putting a real house in a volume the size of a basketball? Simple, just increase the density of space-time within that abstract volume. That will increase the number of quantum states possible just like increasing the resolution of your computer screen. But what do we mean when we say "space is dense"? Since the vacum is matters "opposite", we would probably conclude that space would be "denser" where matter is not. So we might say that within a "black-hole" there is theoretically "no space". A black hole would then indeed be a hold within space-time, a tear in the fabric of reality for example. But this may not be the case. It could be that a black hole is a place were the density of space is so high as to be exactly "solid" space-time. In this respect matter flows into a black hole and then becomes converted to "space-time", which then slowly and inexorably flows outward. Space-time is being generated by a black-hole by the conversion of matter to space-time.
If space-time is a substance of some kind, and all matter is just some configuration of it, then that would explain why we cannot move faster than light. This would be the case if we were somehow made of configurations and vortices of "air". Since we being made of "air", we could not move faster than sound right? Of course doesn't the speed of sound vary with the density of air? Would not the speed of light vary with the density of space-time? Of course it does, this was Einsteins great find, that light travels along a space-time geodesic. The geodesic caused by the "density" of space-time.
Based on all these analogies, I don't see why we have to think about the fourth dimension at all. We just need to imagine space-time as a volume with varying densities. Within a high density of space-time, you can have more matter, and more quantum states. It is abstract I know, but for my mind it works. Is there a reason that these analogies can be viewed as "wrong"? I'm willing to take an alternate view.
These stories always say it was Einstein's great blunder and it has been vindicated, but it really hasn't. The reason Einstein put it in was that he couldn't find any solutions to his equations that resulted in a static universe. (At the time, Hubble's revolutionary results on the recession of distant galaxies had not been completed, so it was thought the universe must be static) All of his model universes were expanding or contracting. So he added the constant to balance out the contraction in his favoured model (which was also closed, another historical assumption in cosmology that has been disposed of).
OK, but the cosmological constant we see now is being used to explain the _acceleration_ of the universe, nothing like what Einstein put the constant in for. His blunder wasn't really the constant, it was the assumption that the universe was static, which turned out to be totally wrong.
But you have to admire Einstein - out of pure thought and mathematics he produced a theory which is still held up as a foundation of modern physics, even though practically every cosmological observation was made years after he published it (and all the observations have supported the theory to great accuracy). Compare this to, say, quantum mechanics, where many theorists struggled for decades to explain observations that had already been made, and Einstein's one-man theory is truly impressive.
If you take a snapshot of the universe, if you discount its expansion, then the existence of dark energy, remnant of the big bang, is requisite to explain certain phenomena and balance out equations.
Why is it weird these two are similar?
Using density as an analogy, as you have in your post, I couldn't help be reminded of the old TARDIS. By increasing the effective density of space-time within a police-box, you could possibly fit enough inside it to resemble that famous timeship.
Who knows - perhaps the travelling in time and the density of space-time have further connections, even?
On topic:
:)
Fudge factor (Einstein) == fudge factor (dark energy/matter)
What exactly is surprising about this? They were/are both added to represent something unknown, a pure speculation which is likely to fall (or be changed to the extreme) by Occams razor as science and knowledge progresses.
http://www.astronomycafe.net/anthol/fudge.html
Einstein retracted his fudge while still alive and I have a suspicion those championing dark matter/energy will have to as well
Slightly off topic:
Hmm was this the first valid and correct reference to Occams razor on Slashdot ever? Probably the first time here it wasn't used in a faulty manner applying it with anti-religious or ideological/political arguments (one would think people would get a clue from the fact that Occams razor was created by a Franciscan friar).
religion != science
Occams razor = intended for scientific theories (given two equally predictive theories, choose the simpler)
Occams razor != rational to apply to religion
*doesn't even need a flameretardant suit*
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Indeed, and science is not like mathematics either. Newton and company were very wrong about this. With math 2+2!=5 (even for extremely large 2 :P), but in science all you have is theories drawn from lots of anecdotal evidence. If the evidence contradics the theory, then the theory is obviously wrong (or the evidence is not what we think it is).
For this reason science and religion are not at odds because they server very difference purposes. Sure, they have some effect on each other, but I can believe that Darwin was a genius and still appreciate the significance of the Genesis creation story.
They don't have mass (any zero mass particle travels at the speed of light) but they do have energy (E=mc^2 doesn't work for a photon...)
The photon energy is taken into account, but it's currently a tiny fraction of the total energy (most of which is dark energy, the rest mostly dark matter - which does obey E=mc^2). If i recall corrrectly, currently the photons (namely the cosmic microwave background) contribute 0.004 of the total energy (starlight probably contributes less, but I could be wrong). In the past, however, photons dominated the energy (photons cooled over time due to redshifting, so they were very hot and energetic in the past).
The world is everything that is the case
I realize that this is probably a stupid question. I haven't had the math or physics yet to really understand probably all the reasons it's a stupid question, so I'll put it out there and see what people have to say on this (slightly) off-topic issue.
Why is it not possible that the universe is simultaneously expanding and contracting?
One question I've had for a while is, why couldn't the universe be shaped in such a way that the force causing accelleration on the expansion of the universe is actually the gravitational force of the universe contracting.
To sort of illustrate my point, think of the game Asteroids. If you fly out of the top of the screen, you appear back on the bottom, and if you fly out the left side of the screen, you appear on the right side. Why couldn't there be some n-dimensional version of that concept in the universe such that as it expands it's actually approaching an earlier state?
Anyway, if this is just the stupidist thing ever, please be kind in saying so. IAONAP (I Am Obviously Not A Physisist).
Famous Last Words: "hmm...wikipedia says it's edible"
There is never "proof" of anything in science. For dark energy, there is good evidence that the acceleration of the universe is expanding, and the cause of that expansion has been dubbed "dark energy", whatever it is. For dark matter, there are a lot of independent lines evidence which consistently indicate there is a great deal of unseen matter in the universe, and we even have some pretty good ideas on what it could be.
There is no "proof" of anything in physics, but the expansion of the universe has been extremely well established in by observations.
Yeah, Google 'compton effect' (and here and here).
Sorry, but there are no existing alternatives to the expansion of the universe. If you had a modicum of physics education, you'd understand why. That is not to say that no such alternative can exist -- see "there is no proof in physics" -- but the evidence in favor of expansion is quite strong and you have to go through far more contortions to get an alternative to work than the current crop of naive crackpot models.
"and Einstein's one-man theory is truly impressive."
Its impressive, but far from being a one-man theory. It was also supported by experiment, namely the famous Michelson-Morley experiment that ruled out a preferred "ether" frame for the propagation of light.Special relativity also drew from works by poincare, lorentz, hilbert, and others. Einstein's greatness was both in bringing everything into one coherent picture, and in having the courage to do so when almost none of his colleagues at that time believed a word of it.