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Entangled toy universe shows time may be an illusion

newscientist.com

1–10 of 53 posts

Re: Entangled toy universe shows time may be an illusion

#2
Question: Why do some physicists believe it's a problem that physics isn't unified? It seems odd to assume that just because throughout history we've unified more and more concepts that all of physics can be unified. What if there's a limit? It's interesting to think that 100,000 years from now, physicists will still be working on the problem since no one would know it's impossible.

Re: Entangled toy universe shows time may be an illusion

#3

Question: Why do some physicists believe it's a problem that physics isn't unified? It seems odd to assume that just because throughout history we've unified more and more concepts that all of physics can be unified. What if there's a limit? It's interesting to think that 100,000 years from now, physicists will still be working on the problem since no one would know it's impossible.

It's not odd. To me it is only logical to assume that if we can explain most physical phenomena, the trend may very well be extended to the rest of them. Besides, one can find a surprising amount of symmetry, simplicity and beauty in the Universe.

Note: I left the "some physicists" part of your question out of the answer because some physicists would believe in anything.

Re: Entangled toy universe shows time may be an illusion

#4

Question: Why do some physicists believe it's a problem that physics isn't unified? It seems odd to assume that just because throughout history we've unified more and more concepts that all of physics can be unified. What if there's a limit? It's interesting to think that 100,000 years from now, physicists will still be working on the problem since no one would know it's impossible.

Because physicists believe in parsimony?

Less flippantly, simply that if the two (on their own, staggeringly accurate) main theories we have about how the universe works are as fundamentally incompatible as the ones we've got, then there's probably something we don't yet understand about the thing they're describing.

The search for a ToE isn't so much about "unifying" QM and Relativity as it is about figuring out what it is that we don't yet understand about the universe that allows them both to be as true as they appear.

Re: Entangled toy universe shows time may be an illusion

#6

Question: Why do some physicists believe it's a problem that physics isn't unified? It seems odd to assume that just because throughout history we've unified more and more concepts that all of physics can be unified. What if there's a limit? It's interesting to think that 100,000 years from now, physicists will still be working on the problem since no one would know it's impossible.

You either believe in natural or supernatural explanations for the universe. If you accept the latter then the discussion is moot. If you're a scientist your approach is the first.

It is difficult, perhaps impossible, to come up with a philosophically sound logically consistant explanation for natural phenomenon which isn't unified and connected at a fundamental level. Two incompatible sets of natural explanations are vastly less likely than one unless we're falling back on superstition again.

Hence on some level there will be a unified way of approaching and talking about physical phenomena. Now, is that underlying consistent theory achievable? Well that's a different question. If the unified explanation for all natural things, at its heart, relies on physics we just don't have access to - either it's too small scale for us to ever probe, or too large scale, or no longer manifested at this point in the universe's life (there are examples of this I could describe but that'd make this post too long) - then of course we would not ever get to a satisfactory scientific account which is unified.

But efforts to get there tend to reveal other interesting things so are worthwhile even if we never achieve the final goal.

Plus because it's so specialized and inaccessible to the layman, the degree to which there's already tremendous consistency and unification in our theories of the underlying nature of things is dramatically underappreciated by most people.

Re: Entangled toy universe shows time may be an illusion

#7

I didn't read the article because I can never wrap my mind around anything to do with the true nature of time... But it is kind of beautiful to think that all of human history took place during an 'illusion'.

This is one of those cases where the poetic language used to try to explain complex phenomena to lay persons is unhelpful. It doesn't really mean illusion in any sense consistent with what people might imagine that to mean.

Indeed it's not really that revelatory. "Experiment agrees with what we already pretty much know" would have been less interesting.

Re: Entangled toy universe shows time may be an illusion

#8

Question: Why do some physicists believe it's a problem that physics isn't unified? It seems odd to assume that just because throughout history we've unified more and more concepts that all of physics can be unified. What if there's a limit? It's interesting to think that 100,000 years from now, physicists will still be working on the problem since no one would know it's impossible.

You either believe in natural or supernatural explanations for the universe. If you accept the latter then the discussion is moot. If you're a scientist your approach is the first. It is difficult, perhaps impossible, to come up with a philosophically sound logically consistant explanation for natural phenomenon which isn't unified and connected at a fundamental level. Two incompatible sets of natural explanations ar…

It is difficult, perhaps impossible, to come up with a philosophically sound logically consistant explanation for natural phenomenon which isn't unified and connected at a fundamental level. Two incompatible sets of natural explanations are vastly less likely than one unless we're falling back on superstition again.

Really? Ancient philosophers argued that it's vastly less likely for there to be such a huge distance separating celestial bodies than whatever their pet theory of the day was. Or that it's vastly less likely for planets to travel in ellipses, because circles were "so perfect." Throughout history, time and time again, humans seem to have a problem accepting that the imagination of nature is far greater than that of man.

Plus because it's so specialized and inaccessible to the layman, the degree to which there's already tremendous consistency and unification in our theories of the underlying nature of things is dramatically underappreciated by most people.

I'm trying, but unfortunately you've given no examples.

Re: Entangled toy universe shows time may be an illusion

#9
Time is weird stuff. When you can tell what altitude your atomic clock is by the offset in its notion of time with the clock at your side, you start to get an inkling about that.

The professor who taught quantum mechanics at USC when I was there used to joke that God told Adam and Eve that it took 7 days to create the universe, but we know from our observations that it was closer to 14 billion years. Given these two data points we can calculate how close to the speed of light God was travelling when he created the universe ...

Interesting to think of time as actually stopped though to an outside observer. Not sure what a photon is when it isn't moving at all, perhaps a point with an electric field and equal and perpendicular magnetic field.

Re: Entangled toy universe shows time may be an illusion

#10

Earlier quoted context omitted.

You either believe in natural or supernatural explanations for the universe. If you accept the latter then the discussion is moot. If you're a scientist your approach is the first. It is difficult, perhaps impossible, to come up with a philosophically sound logically consistant explanation for natural phenomenon which isn't unified and connected at a fundamental level. Two incompatible sets of natural explanations ar…

It is difficult, perhaps impossible, to come up with a philosophically sound logically consistant explanation for natural phenomenon which isn't unified and connected at a fundamental level. Two incompatible sets of natural explanations are vastly less likely than one unless we're falling back on superstition again. Really? Ancient philosophers argued that it's vastly less likely for there to be such a huge distance…

> Ancient philosophers argued that it's vastly less likely for there to be such a huge distance separating celestial bodies than whatever their pet theory of the day was.

Is it me or is that a bit handwavy? The Greeks or whoever else got things awfully right and other things terribly wrong. We have the benefit of hindsight so we can point at the latter category. It doesn't negate the former.

Seems like you could take any statement and say "oh yeah? well the ancients got stuff wrong!"

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