Lambda-CDM theory - Woo or not?

[Tubbythin]

It means that the attractive form of gravity shows up in a lab, unlike your invisible friends, and unlike your claims of 'repulsive gravity".

It meant no such thing. Your sentence didn't make any sense whatsoever (largely due to your random insertion of ").

There is an empirical link between gravity and acceleration. There is no empirical link between "inflation" and acceleration, or any empirical link between dark energy and acceleration.

How could you possibly know? You have no idea what any of the key terms in the above to sentences actually mean.

Nope. Gravity shows up on Earth.

What do you mean by "nope"? Are you rejecting that scientific progress comes from formulating hypothese and theories to match data then testing them against new data?

Your invisible friends are no shows in the lab.

I don't have any invisible friends. Try again.

There's an empirical cause/effect relationship between "acceleration" and you invisible friends that you forgot to bother to demonstrate.

I don't have any invisible friends, try again.

Gravity is easy to "qualify" in an ordinary manner.

Not on a lab scale it isn't. It's very difficult. It took a fundamental discovery in nuclear physics (bizarrely) before we could test GR in the lab. That didn't come until 1960.

We can see it do it's thing in every experiment we might come up with.

No we can't. It is of no significance whatsoever in any particle physics experiment.

There is no qualified link between acceleration and your dynamic metaphysical duo. That's the part you don't want to cop to.

I don't have a dynamic metaphysical duo. Of course I'm not going to cop to it.

 

[Perpetual Student]

This is "*"*AMAZING*"*".

 

[Tubbythin]

We can "empirically experiment" with "gravity" and specifically the "attractive" aspects of gravity right here on Earth, and gravity consistently shows up in the lab here on Earth.

Actually Michael, there was none of your precious lab-based evidence favouring GR over NG until 5 years after Einstein died.

 

[ben m]

No. His lambda was "qualified" in the lab. Gravity always shows up in the lab.

This has always been, and will always be, a dumb way to think about it---lab vs. non-lab. But I'll play along.

You seem to think that "attractive gravity"---i.e. "apples fall down"---somehow tests the lambda term of GR. It doesn't. It tests the 00 term of the Einstein tensor---nothing else. It doesn't test the energy flux terms, it doesn't test the pressure terms, it doesn't test the momentum terms. And it certainly doesn't test the cosmological-constant term.

(Why did Einstein put these untested terms in, when only one term was needed to explain "attractive gravity"? To make the math work; it's a mathematical theory. Higher-order GR terms were eventually tested by LAGEOS, Gravity Probes A and B, Eotvos and related experiments, Lunar Laser Ranging, and astronomical observations, most long after Einstein's death.)

Why don't you show us a "lab experiment", one that Einstein knew about, that could tell the difference between lambda=0, lambda = -10^-20, and lambda = + 10^-20. This is a direct question, Michael---I will ask you to answer it directly.

 

[Michael Mozina]

IMO, I'd take that as N/A.

Um, how exactly can it be N/A that you stuck invisible magic keebler elves into lambda?

 

[Perpetual Student]

The history of events is quite clear here. Einstein saw that his GR equations inevitably led to a collapsing universe. But, observations of that era showed no collapsing universe, so Lambda was introduced (out of his head -- as MM would say) to account for what was thought to be a static universe. Thus lambda was a "metaphysical bunny not showing up in the lab." There is rich irony in that MM would object to lambda to account for an accelerating universe today but embrace lambda to account for a static one, when the two applications of lambda are identical in that they are a consequence of observations of the times. It is understandable when one is incapable of understanding GR because of intellectual and educational limitations. But it is not understandable when one is incapable of grasping simple historical events and elementary logic.

 

[Michael Mozina]

This has always been, and will always be, a dumb way to think about it---lab vs. non-lab. But I'll play along.

You seem to think that "attractive gravity"---i.e. "apples fall down"---somehow tests the lambda term of GR. It doesn't. It tests the 00 term of the Einstein tensor---nothing else. It doesn't test the energy flux terms, it doesn't test the pressure terms, it doesn't test the momentum terms. And it certainly doesn't test the cosmological-constant term.

It doesn't "test" anything ben, it's simply an "empirical possibility". Gravity can easily be empirically linked to "acceleration". It's therefore "possible" that mass outside of our visible universe "attracts" the mass inside out universe and "accelerates" that mass over time.

Magic invisible elves are *NOT* empirically linked to acceleration, so there is no point in having them play the leading role in lambda.

You are completely ignoring the qualification aspect between "acceleration" and "insert theory of choice". There is a clear empirical link between "gravity' and "acceleration". There is a clear empirical link between EM fields and plasma acceleration too. There is no empirical link between evil invisible energies and acceleration. Yes or no do you accept this distinction?

 

[Tubbythin]

Um, how exactly can it be N/A that you stuck invisible magic keebler elves into lambda?

Its the same N/A in the way that the answer to the question: "So did you stop beating your wife?" would be N/A

 

[Michael Mozina]

The history of events is quite clear here. Einstein saw that his GR equations inevitably led to a collapsing universe. But, observations of that era showed no collapsing universe, so Lambda was introduced (out of his head -- as MM would say) to account for what was thought to be a static universe.

Correct.

Thus lambda was a "metaphysical bunny not showing up in the lab."

Incorrect. Gravity and acceleration are clearly linked in the lab and there is a clear "qualification" between proposing external (to the visible universe) mass, and "acceleration". We might complain that it has no observational support, or flies in the face of observation, but at no time did was it "metaphysical". It could turn out to be be falsified *by observation* and at that point it can become "bunny math" that no longer has any purpose. That is in fact what happened to Einstein from his perspective when he found out that "spacetime" was expanding. He took out his math bunnies and left it alone. At no time however was it "metaphysical" in any way. His math bunnies were well "qualified" even if they were "falsified" by later observation. It's not even clear that they were actually falsified by observation, or that they were actually math bunnies at all, which is of course a great irony all things considered.

 

[Ziggurat]

The funny thing about this exchange for me is that it reveals Michael's bizarre respect (if that's the right word) for authority figures, provided that they're dead. Birkeland was a visionary, and his mistakes are forgotten. Alfven was a genius, and progress in plasma physics since him get ignored. And Einstein's work was empirically "qualified" (whatever the hell that means) but modern cosmology is not. The irony of Michael's treatment of Einstein is multi-faceted: Michael doesn't understand GR itself, he doesn't understand that it's primarily a mathematically-justified theory that only gained experimental evidence long after it was formulated, and he doesn't understand that Einstein made unjustified assumptions with lambda. This deference and incomprehension leads Michael to claim he's supporting Einstein when in fact the position he is trying to take is directly contradicted by Einstein's actual work. But he can't bring himself to claim that Einstein was wrong about anything (even though he clearly was, and even admitted so), just like he can't admit Alfven or Birkeland were wrong. It's quite strange. The sad part is that this mythologizing deprives them of their humanity, and the enforced ignorance required to maintain this illusion limits appreciation of their true accomplishments.

 

[GeeMack]

It doesn't "test" anything ben, it's simply an "empirical possibility". Gravity can easily be empirically linked to "acceleration". It's therefore "possible" that mass outside of our visible universe "attracts" the mass inside out universe and "accelerates" that mass over time.

Magic invisible elves are *NOT* empirically linked to acceleration, so there is no point in having them play the leading role in lambda.

You are completely ignoring the qualification aspect between "acceleration" and "insert theory of choice". There is a clear empirical link between "gravity' and "acceleration". There is a clear empirical link between EM fields and plasma acceleration too. There is no empirical link between evil invisible energies and acceleration. Yes or no do you accept this distinction?

Since Michael's argument depends on words and phrases which he refuses to define, the above comment may be translated into the following:

It doesn't "#$^!" anything ben, it's simply an "%&@$%&&". Gravity can easily be empirically linked to "$%!^". It's therefore "%!#$%!" that mass outside of our visible universe "*@$%%@" the mass inside out universe and "#%%^!%" that mass over time.

Magic invisible elves are *NOT* empirically linked to acceleration, so there is no point in having them play the leading role in lambda.

You are completely ignoring the qualification aspect between "^%@%@" and "#$@%!". There is a clear empirical link between "&@%^" and "*@#%^@%". There is a clear empirical link between EM fields and plasma acceleration too. There is no empirical link between evil invisible energies and acceleration. Yes or no do you accept this distinction?

​

 

[Ziggurat]

Incorrect. Gravity and acceleration are clearly linked in the lab and there is a clear "qualification" between proposing external (to the visible universe) mass, and "acceleration". We might complain that it has no observational support, or flies in the face of observation, but at no time did was it "metaphysical". It could turn out to be be falsified *by observation* and at that point it can become "bunny math" that no longer has any purpose.

My goodness. If I didn't know better, I could read this as an uncharacteristically coherent defense... of dark energy.

 

[GeeMack]

Gravity and acceleration are clearly linked in the lab and there is a clear "qualification" between proposing external (to the visible universe) mass, and "acceleration". We might complain that it has no observational support, or flies in the face of observation, but at no time did was it "metaphysical". It could turn out to be be falsified *by observation* and at that point it can become "bunny math" that no longer has any purpose. That is in fact what happened to Einstein from his perspective when he found out that "spacetime" was expanding. He took out his math bunnies and left it alone. At no time however was it "metaphysical" in any way. His math bunnies were well "qualified" even if they were "falsified" by later observation. It's not even clear that they were actually falsified by observation, or that they were actually math bunnies at all, which is of course a great irony all things considered.

... is an argument which, because of Michael's refusal to define his terminology, means exactly the same thing as...

Gravity and acceleration are clearly linked in the lab and there is a clear "&#*#&*" between proposing external (to the visible universe) mass, and "@^@%^". We might complain that it has no observational support, or flies in the face of observation, but at no time did was it "*#^%*%&". It could turn out to be be falsified *by observation* and at that point it can become "*#%&@" that no longer has any purpose. That is in fact what happened to Einstein from his perspective when he found out that "@#$%^@" was expanding. He took out his math bunnies and left it alone. At no time however was it "$^*#&" in any way. His math bunnies were well "^#%&@" even if they were "*#&#&" by later observation. It's not even clear that they were actually falsified by observation, or that they were actually math bunnies at all, which is of course a great irony all things considered.

 

[Michael Mozina]

The funny thing about this exchange for me is that it reveals Michael's bizarre respect (if that's the right word) for authority figures, provided that they're dead. Birkeland was a visionary, and his mistakes are forgotten. Alfven was a genius, and progress in plasma physics since him get ignored. And Einstein's work was empirically "qualified" (whatever the hell that means) but modern cosmology is not. The irony of Michael's treatment of Einstein is multi-faceted: Michael doesn't understand GR itself, he doesn't understand that it's primarily a mathematically-justified theory that only gained experimental evidence long after it was formulated, and he doesn't understand that Einstein made unjustified assumptions with lambda. This deference and incomprehension leads Michael to claim he's supporting Einstein when in fact the position he is trying to take is directly contradicted by Einstein's actual work. But he can't bring himself to claim that Einstein was wrong about anything (even though he clearly was, and even admitted so), just like he can't admit Alfven or Birkeland were wrong. It's quite strange. The sad part is that this mythologizing deprives them of their humanity, and the enforced ignorance required to maintain this illusion limits appreciation of their true accomplishments.

I didn't put anyone on any pedestals Zig, or claimed anyone was infallible. In fact it seems like only your side of the aisle seems to think their own work is "infallible" and incapable of being criticized. Exactly the opposite is true. Einstein's "mistake" in introducing a positive lambda was never an "unqualified" mistake. It may have been falsified by observation (at least a static universe), but the basic idea always had empirical merit. At no time did he propose a "cause/effect" relationship between "acceleration" and lambda that was not well "qualified".

Your theories however are completely *devoid* of empirical qualification. They are completely ad hoc mental constructs without any sort of scientific precedent. You simply "made them up" and stuffed them in there into lambda, in a purely ad hoc manner. It's just like sticking magic invisible faeries in there and claiming it's still "physics". It's nothing of the sort.

 

[ben m]

It doesn't "test" anything ben, it's simply an "empirical possibility". Gravity can easily be empirically linked to "acceleration". It's therefore "possible" that mass outside of our visible universe "attracts" the mass inside out universe and "accelerates" that mass over time.

Magic invisible elves are *NOT* empirically linked to acceleration, so there is no point in having them play the leading role in lambda.

You are completely ignoring the qualification aspect between "acceleration" and "insert theory of choice". There is a clear empirical link between "gravity' and "acceleration". There is a clear empirical link between EM fields and plasma acceleration too. There is no empirical link between evil invisible energies and acceleration. Yes or no do you accept this distinction?

An anecdote. In oral exams, you get to a point---I've been there from both sides, unfortunately---where the examinee obviously can't say anything intelligent on a certain topic. The examiner allows them to flail for a while hoping that they'll stumble back to reality. Then the examiner allows them to flail a little further, so that they'll be appropriately ashamed of themselves and study harder next time. Then the examiner ends the misery by saying, "OK, um, that's enough of THAT, let's go to the next question." (And the audience will want to shout, "Mercy! Mercy!" or "Let it die!")

Forget it Michael. We've all seen enough of that. (Mercy! Mercy!) You have no idea what you are talking about. (Let it die!) Ready for the next question?

(Remeniscing: the "student" side was when my committee asked me to derive the differential Coulomb-scattering cross section on the blackboard; I got as far as writing down two coupled differential equations, then choked spectacularly. Ten minutes of silent staring at the board. <shiver>.)

 

[Tubbythin]

It doesn't "test" anything ben, it's simply an "empirical possibility". Gravity can easily be empirically linked to "acceleration". It's therefore "possible" that mass outside of our visible universe "attracts" the mass inside out universe and "accelerates" that mass over time.

Ever heard of the Copernican Principle Michael? If not, look it up.

Magic invisible elves are *NOT* empirically linked to acceleration, so there is no point in having them play the leading role in lambda.

Please find me one peer reviewed paper on cosmology reporting the existence of "magic invisible elves". Otherwise, stop making rubbish up Michael. You are humiliating yourself.

You are completely ignoring the qualification aspect between "acceleration" and "insert theory of choice". There is a clear empirical link between "gravity' and "acceleration". There is a clear empirical link between EM fields and plasma acceleration too. There is no empirical link between evil invisible energies and acceleration.

Erm. Michael, that's a term you just made up. Of course nobody believes in it. Why would you think anybody would?

Yes or no do you accept this distinction?

I know the distinction between physics and arguments by Michael Mozina which consist of making up stupid names and then asking whether people know of any link between the names he just made up and "empirical physics".

 

[Tubbythin]

I didn't put anyone on any pedestals Zig, or claimed anyone was infallible. In fact it seems like only your side of the aisle seems to think their own work is "infallible" and incapable of being criticized. Exactly the opposite is true. Einstein's "mistake" in introducing a positive lambda was never an "unqualified" mistake. It may have been falsified by observation (at least a static universe), but the basic idea always had empirical merit. At no time did he propose a "cause/effect" relationship between "acceleration" and lambda that was not well "qualified".

Your theories however are completely *devoid* of empirical qualification. They are completely ad hoc mental constructs without any sort of scientific precedent. You simply "made them up" and stuffed them in there into lambda, in a purely ad hoc manner. It's just like sticking magic invisible faeries in there and claiming it's still "physics". It's nothing of the sort.

Do you enjoy making up alternative histories that have no truth whatsoever. I hadn't realise it wasn't just science where you just must rubbish up until recently.

 

[W.D.Clinger]

Oh, the irony:

It doesn't "test" anything ben, it's simply an "empirical possibility". Gravity can easily be empirically linked to "acceleration". It's therefore "possible" that mass outside of our visible universe "attracts" the mass inside out universe and "accelerates" that mass over time.

It sounds as though Michael Mozina is conflating two different solutions of the Einstein field equations^WP:

1. Einstein's original attempt, which involved no lambda but relied on a mathematical trick (matter outside the visible universe) to stabilize the solution.
2. Einstein's static solution of 1917, in which Einstein added the magic (critical) value of lambda that stabilizes staticizes a de Sitter model with closed space.

ETA: Einstein's static de Sitter solution with the critical value of lambda was unstable, so my use of "stabilize" was particularly unfortunate.

 

[ben m]

Let it die! Mercy! This is pointless, everyone. Michael is now taking a fictional version of Albert Einstein, giving him a fictional version of a gravity theory, pretending to apply this theory to data that he doesn't understand, and splitting hairs about a purported difference between this fictional theory that he likes and a another fictional theory that he doesn't like.

 

[Tubbythin]

Oh, the irony:

It sounds as though Michael Mozina is conflating two different solutions of the Einstein field equations^WP:

1. Einstein's original attempt, which involved no lambda but relied on a mathematical trick (matter outside the visible universe) to stabilize the solution.
2. Einstein's static solution of 1917, in which Einstein added the magic (critical) value of lambda that stabilizes a de Sitter model with closed space.

Is he not also suggesting we're at the centre of the universe?