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No, negative masses have not revolutionized cosmology

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Re: No, negative masses have not revolutionized cosmology

#81

Earlier quoted context omitted.

Dark energy is the cosmological constant introduced by Einstein. So that criticism is rather ironic.

Actually, a cosmological constant is derivable from the Standard Model. But it's off by a very remarkable amount. Dark energy is the observation that that the Standard Model mispredicts the cosmological constant, so there must be something wrong with it.

> cosmological constant is derivable from the Standard Model.

Well.. not really directly "derivable."

To be more specific, the "problem" is: when using the the "Standard Model of particle physics" (which is confirmed time and again for anything we do with the particles, and which, of course, we anyway know that is still inconsistent with the General Relativity model) to calculate the "renormalized value of the zero-point vacuum energy density" as the contribution to the cosmological constant, the number is calculated that, to our present understanding of the factors involved, can't match our cosmological measurements. Note that that "renormalization" process is a method used otherwise to "extract" the finite answer from the divergent expression (i.e. one that would involve infinities). Applying such method in this derivations gets the "wrong" number.

It's much less surprising when it is stated precisely. Attempting specific derivations in which the "infinities" are "avoided" by using a specific approach which for some other cases works, we discover that in these derivations the mentioned approach "doesn't work", that is, that something is missing in an attempt to compare two theories for which we anyway know that they aren't consistent when they have to be applied together.

https://arxiv.org/abs/1205.3365

Luckily, these inconsistencies aren't something that prevents us to use both General Relativity and the Standard Model independently to great success. Using them together is needed only to model very extreme conditions like writing the equations for some point inside of the black hole or something like that. And that doesn't disprove black holes in any way: we measured even their collisions(!) using the predictions of the models.

And we can claim already:

http://www.preposterousuniverse.com/blog/2010/09/29/seriousl...

"The Laws Underlying The Physics of Everyday Life Are Completely Understood"

Re: No, negative masses have not revolutionized cosmology

#82
post #79

Earlier quoted context omitted.

> "it’s highly problematic to introduce negative inertial masses because this means the vacuum becomes unstable. If you do this, you can produce particle pairs from a net energy of zero in infinitely large amounts. This fits badly with our observations." Basically, if you mess the the equation, you have to be very sure you aren't simulating something silly. Which is easy to do, unfortunately I've done it often. I sti…

Waaait a minute, isn't that describing something we've already observed - spontaneous creation of virtual particle pairs in a vacuum?

In infinitely large amounts?

Re: No, negative masses have not revolutionized cosmology

#83
post #79

Earlier quoted context omitted.

> "it’s highly problematic to introduce negative inertial masses because this means the vacuum becomes unstable. If you do this, you can produce particle pairs from a net energy of zero in infinitely large amounts. This fits badly with our observations." Basically, if you mess the the equation, you have to be very sure you aren't simulating something silly. Which is easy to do, unfortunately I've done it often. I sti…

Waaait a minute, isn't that describing something we've already observed - spontaneous creation of virtual particle pairs in a vacuum?

We have definitely not observed spontaneous creation of virtual pairs in a vacuum. I do not blame you for thinking so as it is often described this way.

Almost no computation in Quantum Field Theory can be done exactly. What physicists do is using perturbation theory which is very similar to doing Taylor series in introductory calculus. Feynman, in a genius inspiration, found a way to represent the various mathematical terms that occur in these types of calculations as pictures which could be described in words. In this pictorial language, one would say things like "this term correspond to the creation of a virtual pair of particles", etc." The perturbation expansion is a mathematical "trick" done so that we can do obtain approximate results. Each individual term in that expansion has no physical meaning - in spite of the pictorial language used.

Re: No, negative masses have not revolutionized cosmology

#84
post #22
post #17

Earlier quoted context omitted.

If paper in question becomes fodder for the mainstream media (or at least the mainstream scientific media) then there is no reason why they should not have to defend their theory/arguments/speculations publicly in a less than formal peer reviewed forum, especially one of fairly high regard in that subject area.

There is a good reason: we should not be passing judgement on the validity of scientific work based on informal discussions.

Disagree. As just one example, the Solvay conferences of the 1910s-20s. Much of QM was developed by informal discussions, both written and verbal.

Likewise, most of the initial challenges to scientific papers/theories/experimental results happens informally and only later will there be a peer reviewed counter (if the original has not between withdrawn or modified before). Reference the OPERA ftl neutrinos for a recent example.

Re: No, negative masses have not revolutionized cosmology

#85

Earlier quoted context omitted.

It's not disqualified for not being simple, it's disqualified for not making testable predictions. Given two theories, neither of which make testable predictions, the simpler one (and the one that has been studied more thoroughly) is the more reliable. Otherwise, why not just say that the missing mass is unicorns? And the energy driving the accelerated expansion of the universe is the energy of their love? There's no…

The author of the negative mass theory said that it will be testable via the cubic kilometer ice array in Antarctica when it comes online (though I'm not sure how). He mentions it in his chain of 17 tweets that summarize the theory .

I thought he was planning to use the Square Kilometre Array radio telescope which is still in the works, and not to be confused with the Ice Cube neutrino detector which has been operational for several years.

https://cdr.skatelescope.org/

https://icecube.wisc.edu/science/icecube/detector

Re: No, negative masses have not revolutionized cosmology

#86
post #85

Earlier quoted context omitted.

The author of the negative mass theory said that it will be testable via the cubic kilometer ice array in Antarctica when it comes online (though I'm not sure how). He mentions it in his chain of 17 tweets that summarize the theory .

I thought he was planning to use the Square Kilometre Array radio telescope which is still in the works, and not to be confused with the Ice Cube neutrino detector which has been operational for several years. https://cdr.skatelescope.org/ https://icecube.wisc.edu/science/icecube/detector

Yep, you are right - I was confusing the Square Kilometer Array for the Ice Cube neutrino detector. Heres a direct link to his tweet: https://twitter.com/Astro_Jamie/status/1070304980224172033
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