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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%."
what's up with this?
last month scientists proved that they were wrongly using newtonian physics to measure the amount of matter in the universe, but when they changed their equations to einsteinian physics, there was no need of any dark matter to make up 'lost' matter in the universe. as einstein said, 'everything is just-as-it-is.
if all that is true, why does anyone need dark matter to 'prove' the cosmological constant?
regards,
roger born
"always drink upstream from the herd."
Einstein put in the constant as a fudge because he wanted his equation to match the data. At the time people were not aware of the exanding nature of the universe. I don't think he ever liked using the constant, and was relieved when it turned out it wasn't necessary. Everything was neat again.
Yeah... and it may get worse. Here's the story to the best of my knowledge:
Einstein did some calculations and stuff and came up with two potential models of the universe. (Perhaps two solutions to his equations?) One had the universe expanding, the other contracting. Einstein called up some astronomers and asked which it was. They told him to get lost, that the universe was static. So Einstein went back and added the cosmological constant so that it matched "reality." Later Hubble was like "look, y'all, the universe is expanding," and Einstein was like "my bad" and dropped the constant.
But here's the thing: the universe's expansion is accelerating. If it models something like the cosmological constant, that means that the extra force Einstein added must be repellant. This tells me that the model he picked to add the constant to was the contracting one. Which means that I don't see a correspondance to reality.
There might be something deep about why about the same force would take the contracting universe model and make it static would also take the expanding universe model and make it accelerating, but I don't see what it is.
Which means that if they turn out close, I think it's much more likely that it's just a really lucky coincidence rather than the genious of Einstein. Even if there is a deep correspondence, the fact that Einstein added it to an incorrect model to bring it to another incorrect model, and when that incorrect model was found to be incorrect renounced it, pretty much rules out the possibility that this is really an example of his genious.
This is, at least, the reaction I have whenever I read about the cosmological constant... am I totally off-base?
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?)
Wasn't the cosmological constant added by Einstein to have his equations show that the universe WAS NOT expanding. Einstein believed, along with a lot of other physicists at the time, that the universe was static and had existed forever. This was contradicted later by Hubble, and Einstein's original equations showed that Space-Time was expanding at a constant rate so he added a term to cancel the expansion. So if new evidence shows that the universe's expansion is accelerating than shouldn't we say that the cosmological constant's magnitude had the wrong sign? Of course this assumes that the cosmological constant's magnitude was correct in the first place.
Also didnt another study say that dark energy didnt exist and that space-time ripples from the universe's period of hyperexpansion would produce the exact same effects as Dark energy? I think I saw that article on here a while back
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.
> The ancient Greeks calculated Pi within 10%
Actually they did a heck of a lot better than that. Hint: The +/- 10% error bars on pi go from about 2.86 to 3.46.
Remember the old "the bible says pi = 3" joke?
pi/3 = 1.0471975511965977461542144610932.
That's only 4.7%.
The Greeks knew an even better approximation: 22/7.
(22/7)/pi = 1.0004024994347706819758407983415.
That's 0.04%.
The problem was that our estimates of how much matter there was in the universe came out well below what was needed for there to be enough gravity to make the expansion stop and eventually reverse.
But the expansion of the universe doesn't mean that the galaxies are moving away from each other, even though this is a very, very common misconception. It means that the space itself is expanding. See 'superluminal expansion'. Yeah, I don't get it either. Why the hell would space itself be expanding and why would dark energy or matter have anything to do with it?
If the road to hell is paved with good intentions, where does the road paved with evil intentions lead to?
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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I get tired of this description of the Big Bang as an explosion in the usual terms, as in things flying apart out into something, "matter flying off in all directions". It's popular science, and most people wouldn't know what the heck you were talking about if you described it any other way. But, it ought to be restated...
It's an expansion of space, everything that is in space is just going along for the ride.
A visual way to clarify that is to shoot down the idea people have that things cannot recede faster than light. That gets their attention, they all know about Einstein and c. Things cannot move through space faster than light, but space itself puts a distance between things that C can never outpace.
You might only be joking but the quote about God throwing dice is interesting. The idea that something can be truely random was absurd to Einstiein and he might be right. Eventually it might be possible to completely predict object intereaction in a closed system with enough variables. Or crazily, matter/energy interaction anywhere in the galaxy.
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.
Cut the crap. My post had plenty of physics content. Your has none, other than specious comparisons of science to religion. Put up or shut up: scientficially defend an alternative to the Big Bang.
Science is in agreement that space is expanding, and the Compton effect does not account for redshifts.
We know quite a bit about that, actually.
Of course we do. It is quite possible to map out the matter distribution in the galaxy. We have known for a long time that it is a spiral, and now know that it is likely a barred spiral.
Nonsense. I pointed out that we cannot have proof of anything in science, but I also pointed out that there are many things that we are quite sure of, and I gave reasons why. It is all well and good to portray yourself as a reasoned skeptic, but what are your actual justifications? Sorry, but saying "we don't know things for sure" does not justify a claim that we don't know anything about the universe.
Philosophical opinion has no bearing on whether a theory is right or wrong. Only is consistency with experimental reality is what matters. And Big Bang cosmology is extremely consistent with all known observations -- and all known alternatives to it are not.
Furthermore, the Big Bang is not a centrist view, it is quite the opposite: there is no center of the universe in Big Bang theory.
This is more strawman nonsense. Cosmologists do not claim that the universe has a center outside of spacetime, they claim it has no center at all. You are probably one of those people who think that manifolds have to be embedded in higher dimensions to be curved. That is not true: a centerless hypersphere can exist without being embedded within some higher dimensional space in which it has a center.
So, I'm waiting... are you going to reply with some physical reasons why the Big Bang is incorrect? i.e., experiments with which its predictions disagree? Or with alternative theories that account for all of the same observations the Big Bang does? Or are you merely going to respond with more ad hominem attacks, vague handwaving, appeals to your personal philosophy, and a naive skepticism based on ignorance?
This means if you go a billion lightyears in one direction and then stop at point A you should encounter a higher mass density compared to Earth's vicinity. The catch is if you go back from point A to Earth you must also observe an increase in density. So the density of Earth's vicinity must have increased during the trip. But if accelerating expansion is true, the density after the trip must be lower than the initial value. So the idea that density always increases contradicts accelerating expansion, the reason of its proposal.
If you don't want uniform and symmetric density increase, you either need to define a universal origin (breaks relativity) or a modification of GR which explains why less dense volumes beyond horizon attract stronger than more dense volumes inside horizon (also breaks relativity).
Wish I was sober enough to judge whether this makes any sense. Take this explanation with a grain of salt.