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At Multiverse Impasse, a New Theory of Scale

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Re: At Multiverse Impasse, a New Theory of Scale

#121

Post by obruchez »

differentView wrote: post #97
derefr wrote: post #89

Earlier quoted context omitted.

> The discovery of supersymmetric particles would also be extremely shocking to me, since my institution is heavily involved in CERN LHC experiments, and I haven't heard any hints of a discovery yet. Why does an absence of evidence imply that the arrival of evidence would be shocking? They're doing the experiment because they already believe things are this way and they're trying to get evidence to confirm it. If the…

>They're doing the experiment because they already believe things are this way and they're trying to get evidence to confirm it. Hypothesizing is one thing, but to believe without evidence is just blind faith.

Isn't faith blind by definition?

Re: At Multiverse Impasse, a New Theory of Scale

#122

Post by chemunc »

lutusp wrote: post #98
derefr wrote: post #89

Earlier quoted context omitted.

> The discovery of supersymmetric particles would also be extremely shocking to me, since my institution is heavily involved in CERN LHC experiments, and I haven't heard any hints of a discovery yet. Why does an absence of evidence imply that the arrival of evidence would be shocking? They're doing the experiment because they already believe things are this way and they're trying to get evidence to confirm it. If the…

> They're doing the experiment because they already believe things are this way and they're trying to get evidence to confirm it. That's not science, that's confirmation bias. In science, one would want to look for evidence that one's theory is false with as much vigor as a search for evidence that it's true. Science isn't law, and it's not religion. > If they disconfirmed it, that'd be surprising. If they falsified…

I'm not trying to start an argument here, but wouldn't "assuming what they should be proving" be the same as "hypothesizing?" That's a critical point of the scientific method. You don't really design experiments that can both confirm and refute a theory. When an "open-minded" scientist attempts to perform an experiment to test theory, they aren't personally responsible for subsequent theories and experiments that could disprove their results.

Re: At Multiverse Impasse, a New Theory of Scale

#123

Post by Bognar »

ccvannorman wrote: post #118

I once read that "black holes orbiting each other follow the exact same mathematics as electrons orbiting protons", but I was unable to find the direct source. I did find another article comparing black holes to elementary particles: http://www.technologyreview.com/view/413483/could-all-partic...

They would naturally follow the same mathematics, since the formula for gravitational attraction and the formula for electrical attraction are both following the inverse square law.

http://en.wikipedia.org/wiki/Inverse-square_law

Re: At Multiverse Impasse, a New Theory of Scale

#124

Post by dandrews »

MisterMashable wrote: post #74

There's a very subtle undertone of negativity in this article about physics. Before I get into, William Bardeen is not in the same league as 'Surfer Dude and his E8 Theory of Everything' which throws basic facts about representation theory out the window, coming up with 'todalay boogus' arguments which amazes auntie, mommie and magazine editors but a real physicist would instantly dismiss. Bardeen is the real deal. H…

Surfer Dude and his E8 Theory of Everything ... 'todalay boogus' arguments which amazes auntie, mommie and magazine editors but a real physicist would instantly dismiss.

I suppose you're referring to Lisi? Neither he nor E8 were even mentioned in the article. You're both OT and unnecessarily unpleasant.

Re: At Multiverse Impasse, a New Theory of Scale

#125

Post by xrange »

lutusp wrote: post #35
gus_massa wrote: post #30

Earlier quoted context omitted.

I agree. More details: http://en.wikipedia.org/wiki/Velocity-addition_formula If you add two velocities that are less than c, you can never get c, you always get something smaller. 0.8c + 0.3 c ~= 0.887 c (It's smaller than c) At low speeds the effect still exists, but it's negligible. There is an important difference between "it doesn't exist" and "it's so small that if we forget it we will be fine". It's so small t…

> The correction is veeeeery small. Indeed it is. The only place I can think where such a small correction matters is in the GPS system. The accuracy of the GPS system depends on tracking down and eliminating every possible source of error, and to maximize position accuracy, two relativistic effects are accounted for: 1. The time dilation caused by the satellites' velocity, from Special Relativity. 2. The rate of tim…

Does anyone know of a general & special relativity simulator? That is, a program where I can setup various "thought experiments", by placing clocks and masses at various point in space, where they can have various acceleration profiles, and can communicate with each other, and run the scenarios? I never really understood the twins "paradox" and the explanations for the source of the asymmetry seemed hand-wavy and "because".

Re: At Multiverse Impasse, a New Theory of Scale

#126

Post by lutusp »

chemunc wrote: post #122
lutusp wrote: post #98

Earlier quoted context omitted.

> They're doing the experiment because they already believe things are this way and they're trying to get evidence to confirm it. That's not science, that's confirmation bias. In science, one would want to look for evidence that one's theory is false with as much vigor as a search for evidence that it's true. Science isn't law, and it's not religion. > If they disconfirmed it, that'd be surprising. If they falsified…

I'm not trying to start an argument here, but wouldn't "assuming what they should be proving" be the same as "hypothesizing?" That's a critical point of the scientific method. You don't really design experiments that can both confirm and refute a theory. When an "open-minded" scientist attempts to perform an experiment to test theory, they aren't personally responsible for subsequent theories and experiments that cou…

> wouldn't "assuming what they should be proving" be the same as "hypothesizing?"

No, the expression "assuming what you should be proving" has a special semantic meaning -- it refers to a thought process that uses its conclusion to support its investigation, or takes the preferred outcome as a given from the start, without seriously considering alternative explanations.

Hypothesizing means taking existing theory and extrapolating new untested properties, then presumably investigating whether there is any evidence for the hypothesis.

> You don't really design experiments that can both confirm and refute a theory.

On the contrary, the best experiments have the chance to either confirm or refute a hypothesis. The Michelson & Morley ether experiment is a classic of its kind -- its outcome would either confirm or refute the ether as it was imagined to be.

http://en.wikipedia.org/wiki/Michelson%E2%80%93Morley_experi...

> When an "open-minded" scientist attempts to perform an experiment to test theory, they aren't personally responsible for subsequent theories and experiments that could disprove their results.

Not so. An open-minded scientist wouldn't pass up the chance to uncover any positive or negative evidence for or against his theory -- both kinds of evidence contribute to our understanding of nature. Remember the story about Bell Labs engineers Penzias and Wilson cleaning bird droppings from their microwave dish? They did that so someone else wouldn't scoop them by discovering that they had been fooling themselves about the source of the noise in their antenna (which ultimately was identified as the cosmic background radiation, now standing as evidence for the Big Bang).

http://www.aps.org/programs/outreach/history/historicsites/p...

The bottom line? Science isn't law, it's not adversarial, there aren't two competing sides, and a responsible scientist maintains an open mind with respect to evidence both for and against his theories.

Re: At Multiverse Impasse, a New Theory of Scale

#127

Post by derefr »

differentView wrote: post #97
derefr wrote: post #89

Earlier quoted context omitted.

> The discovery of supersymmetric particles would also be extremely shocking to me, since my institution is heavily involved in CERN LHC experiments, and I haven't heard any hints of a discovery yet. Why does an absence of evidence imply that the arrival of evidence would be shocking? They're doing the experiment because they already believe things are this way and they're trying to get evidence to confirm it. If the…

>They're doing the experiment because they already believe things are this way and they're trying to get evidence to confirm it. Hypothesizing is one thing, but to believe without evidence is just blind faith.

If you don't have a higher Bayesian prior on the hypothesis than others, how did you select it out of hypothesis-space as something to test? (http://wiki.lesswrong.com/wiki/Locate_the_hypothesis)

Re: At Multiverse Impasse, a New Theory of Scale

#128

Post by Tloewald »

axilmar wrote: post #45
givan wrote: post #20

I wonder if it's possible to ever find out what our reality is even if we will eventually reach the intellectual and technology necessary because we are part of it and it's probably impossible to have an objective view of the matter.

I do not think that it is possible. Any physical system that can be described by a set of mathematical laws is bound to have some axioms that simply cannot be proven within its context. Godel's incompleteness theorems prove that. Hence, we will never get to the bottom of the reality of our universe.

Not axioms, tautologies (true statements). Godel's incompleteness theorem assumes you know the axioms.

Re: At Multiverse Impasse, a New Theory of Scale

#129

Post by Tloewald »

axilmar wrote: post #45
givan wrote: post #20

I wonder if it's possible to ever find out what our reality is even if we will eventually reach the intellectual and technology necessary because we are part of it and it's probably impossible to have an objective view of the matter.

I do not think that it is possible. Any physical system that can be described by a set of mathematical laws is bound to have some axioms that simply cannot be proven within its context. Godel's incompleteness theorems prove that. Hence, we will never get to the bottom of the reality of our universe.

Not axioms, tautologies (true statements). Godel's incompleteness theorem assumes you know the axioms. Godel doesn't tell us whether we can discover the axioms, although perhaps it implies that as a corollary.

Re: At Multiverse Impasse, a New Theory of Scale

#130

Post by trhway »

Strilanc wrote: post #90
trhway wrote: post #14

>With their field stuck at a nasty impasse of course. Natural thing when a field is dominated by orthodoxy that closes their eyes to everything that they don't want to see. Like yesterday "entangled photon imaging" where what really happens is that a beam modulated by an image heats/excites crystal (with that heating/excitement thus obviously modulated by the image) which generates another beam (thus that another bea…

I'm not sure why you're grouping entanglement in with the multiverse. One of those is a theoretical idea for reducing the Solomonoff complexity of the universe with no clear experimental implications. The other is an integral component of how we predicted and explain experimentally confirmed phenomena like violations of Bell's inequalities, the Elitzur-Vaidman bomb tester, quantum cryptography, and quantum teleportat…

because both violate Occam's razor (and both stem from very specific treatment of superposition). Like in the above mentioned "imaging by entanglement", a closer look at the experiment always reveals explanations for the observed effect without necessity to involve the "magic" of entanglement.
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