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re: Science is debunking itself again
Posted on 9/26/23 at 10:02 am to NC_Tigah
Posted on 9/26/23 at 10:02 am to NC_Tigah
quote:
The term "concerns" implies emotional worries, and in this case, emotion regarding hypothesis contradictions. In deference to the Scientific Method, why concerns?
Lol..here, let me expand your understanding of the English language. Check out noun #2 LINK
quote:
Meanwhile, in a situation where singularity and presingularity physics are unknown, what is the basis of singularity energy/mass assumptions requisite for modeling? What is the presumed source of the preexistent mass/energy?0.
You don't have to go that far back. The solutions to the Einstein Boltzmann equations have limiting values as the scale factor goes to zero. So you just have to start somewhere in that regime. Depends on the frequencies you want to study. a=0.00001 is plenty far back enough for most N body sims. Then once you hit about redshift 50 or so where non-linear growth starts to matter, you take your results from the EB solver, apply the Zeldovich approximation or even better, 2nd order Lagrangian perturbation theory, and start up the N-body simulation until z=0. Although I like to go a little further, just for fun.
If you are interested in the initial conditions for the EB solver I'd refer you to section 7 of Ma & Bertlischenger (sp?) LINK Let me know if you have any trouble understanding the science or if you get hung up on the meaning of any English words.
quote:
Indeed, theoretical physicists such as Robson prepose that the Lambda-CDM Model assumes our universe was created from pure energy. Now, I'll concede I'm not a mathematician, but try as I might, I cannot seem to get E=mc^2 to work in that context, if m=0.
Why would you expect E=mc^2 to strictly apply in a gravitational field? It's derived from special relativity which presume no gravitational field.
1
Posted on 9/26/23 at 10:08 am to Peebles
quote:Come again?
Why would you expect E=mc^2 to strictly apply in a gravitational field
In absence of matter, talk to me about this "gravitational field".
Posted on 9/26/23 at 11:54 am to NC_Tigah
quote:
Come again?
Why would you expect an equation derived under the assumption of Minkowski space-time to apply to other metrics?
quote:
In absence of matter, talk to me about this "gravitational field".
OK. I'll do my best with just text.
Guv + Lambda guv = 8 pi Tuv
Where Guv is the Einstein tensor, Lambda the cosmological constant, guv the metric tensor, and Tuv is the stress-energy tensor without any contributions from matter, just like you asked for. Units are defined such that G=1, c=1
That should about cover it.
This post was edited on 9/26/23 at 12:26 pm
Posted on 9/26/23 at 12:41 pm to Mo Jeaux
quote:
Well, I do know that Jesus himself told us not to judge others, but hey, maybe you know better than he does. Carry on.
Ohhh you've been reading books about the Bible by people who hate the Bible...
Posted on 9/26/23 at 12:46 pm to DisplacedBuckeye
quote:
You did the same earlier in the thread. Calm down.
It's one thing to strike up a conversation, it's another to jump in in order to say someone is stupid and trolling, which I didn't deserve. It's pointless IMO
Posted on 9/26/23 at 12:47 pm to Peebles
quote:Does it?
That should about cover it.
My impression is Guv = Tuv simply describes how matter and energy (which are already assumed present) affect the curvature of spacetime and how matter and energy are conserved.
Lambda guv adds a dark energy constant which is obviously presumptive of its preexistence.
It's an interesting precept, but of course accounts for neither the creation of energy or matter.
Posted on 9/26/23 at 1:34 pm to NC_Tigah
quote:
My impression is Guv = Tuv simply describes how matter and energy (which are already assumed present) affect the curvature of spacetime and how matter and energy are conserved.
Guv = Tuv describes the curvature of space-time.
Div Tuv tells us how the stress-energy tensor evolves in response to that curved-space time. The Div term is only the usual Cartesian divergence for flat space-times, so it has terms like you would find in taking the divergence of a tensor in a non-Cartesian coordinate system. With these terms added, you can't write things so everything is to the right-hand side of a d/dx_n, thus, no general conservation law.
It's not even straightforward to define what it means to have energy conservation under GR. In the classical world we would have
d/dt T0b + div Tab = 0
where T0b is the time component of the stress energy tensor. T0b would be our conserved energy and 3-momentum, because it is the time component. But under GR, we are free to define our coordinate system in any manner we choose, so we could choose a coordinate system where time is not split off from the other three dimensions, and then to speak of energy conservation becomes meaningless. We generally work with GR using coordinates where time is separate ("3+1"), but that's just out of convenience. It's easier for us to wrap our human brains around it that way.
There are special vector fields calling "Killing vector fields" that when multiplied with the stress-energy tensor, you can get a conservation law. But then you just have a conservation law relative to that particular Killing vector field.
quote:
Lambda guv adds a dark energy constant which is obviously presumptive of its preexistence.
Not really. There are multiple lines of observational evidence in favor of an accelerating expansion rate. And most theories that can account for it without a cosmological constant presume some other sort of dark energy that could vary in time. The only other way to account for it would be to presume the Earth is in some special region of the Universe and/or the Universe is way less homogeneous than we think it is. Application of Occam's razor leaves us with a cosmological constant. I'm not saying I'd bet my life on it, but the statement "which is obviously presumptive of its preexistence" isn't supported.
quote:
It's an interesting precept, but of course accounts for neither the creation of energy or matter.
The Friedman equations tell us what the relative balance of dark energy / matter / radiation / curvature there are in the Universe. Curvature is almost certainly zero. The other three aren't.
Addendum: inferring the existence of dark energy isn't as crazy as it sounds. All we are doing is saying there must exist a form of energy with negative pressure. Pressure, here, is as it relates to GR and the vast scales of the Universe. At that level the familiar pressure found in baryonic gasses in terrestrial settings is dwarfed by the effect of gravity. Now pressure is an *attractive* force as it is a source term in Tuv. Every class of matter/energy has a particular ratio of pressure to density. For radiation it is 1/3. For baryonic matter and dark matter we use zero, since, as I pointed out, the pressure due to particles bouncing off one another is negligible at cosmic scales. All we are doing with dark matter is saying there exist some form of energy where that ratio is -1. And if such a form of energy exists, it would have a *repulsive" gravitational force due to negative pressure and thus should be spread evenly throughout the cosmos. I will give you what is probably a horrible analogy but it's the best I can do. Imagine you are a sufficiently intelligent fish in the ocean. The only states of matter you are directly familiar with are liquid and solid. But, by observing the patterns of waves on the surface (or I dunno, use your imagination), you infer the existence of a third state of matter.
This post was edited on 9/26/23 at 2:07 pm
Posted on 9/26/23 at 2:43 pm to Peebles
quote:Fair enough. I did presume we're not occupying a mystically dissociated region of the Universe or components of a simulation FTM.
the statement "which is obviously presumptive of its preexistence" isn't supported.
quote:Which to me is fascinating in and of itself.
Curvature is almost certainly zero.
---
The more general point though, is we know enough to know there are things we don't know. But in many cases, we don't even know enough to know what those things are.
Which brings this back to the term "concern".
You're dismissive of the injection. I'm not. It isn't a matter of my familiarity with language or yours. It's a matter of tolerance of it, and IMO there is far too much recent history in science and medicine to blow off implications of the term, even if its use was inadvertent.
Observations appearing nonconcordant to a hypothesis should never register as "concerning," unless there is secondary damage associated with continuation of the hypothesis itself. E.g., a medical intervention found in certain observations to demonstrate unexpected harm.
Yet, all too often in 21st century, work emotional vesting (inevitably tied to funding, consensus desire, or both) drives research, writing, and subdues antithetical observation in favor of consensus.
Whether that translates to ridiculous explanations of cyclical atmospheric CO2 ice age flux, or Covid derivation genetics, vax effects, or ridiculous claims of zoonotic origin, it is increasingly tolerated in research, and undermines science.
This post was edited on 9/26/23 at 2:57 pm
Posted on 9/26/23 at 2:58 pm to NC_Tigah
Seriously? If you would like to nitpick about word use in scientific literature and entertain the absurd notion that a large portion of science is in error simply because you can not understand the meaning of a word that scientists use, talk with someone else.
This post was edited on 9/26/23 at 3:19 pm
Posted on 9/26/23 at 3:10 pm to Peebles
quote:
All I can do is point you to the second noun definition of the word "concern"
quote:I've been rather civil to this point. I tried. I supposed a more productive exchange might result. Obviously I was wrong. Noted.
a large portion of science is in error simply because you can not understand the meaning of a word that scientists use
This post was edited on 9/27/23 at 11:54 am
Posted on 9/26/23 at 3:14 pm to Herooftheday
quote:
It's one thing to strike up a conversation
Is that what you were doing? By your own admission, you were "harassing" me. To be clear, I'm fine with it. Just wondering why you're so touchy about this dude's response to you.
Posted on 9/26/23 at 3:18 pm to NC_Tigah
quote:You are apparently here to nitpick about word choice and feelings. I do not find that productive. If you find my not finding that productive to be lacking in "civility", then I apologize, from the very bottom of my heart.
productive exchange
Posted on 9/26/23 at 3:31 pm to DisplacedBuckeye
quote:
Just wondering why you're so touchy about this dude's response to you.
I didn't appreciate it getting personal. Why are we talking about this? I've heard more from you than that guy. Hasn't said anything in fact
The scope of my "harassing" you was a line of questions that someone would expect from a religious person. And you bit by pointing it out. It was in jest. I was mocking the stigma.
quote:
To be clear, I'm fine with it
You weren't harassed. I was mocking the stigma of Christianity. You couldn't possibly have been offended by it. I only said that to clue you in.
Posted on 9/26/23 at 3:41 pm to Peebles
quote:No nitwit, I'm now here to point out that your knowledge of the English language lags what you think you understand of it.
You are apparently here to nitpick about word choice and feelings.
quote:There are concerns that these observations are in tension ...
There are concerns that these observations are in tension
There are worries that these observations are in tension ...
There is hand-wringing that these observations are in tension ...
There are frets that these observations are in tension ...
There is gnashing of teeth that these observations are in tension ...
All have similar/identical meaning. Got it?
The use of the word "concerns" in the author's context had nothing to do with business interest, or responsibility. If it did those terms would be interchangeable. They aren't.
Nitpicking is not the game, Hoss.
I'm not the one who imagined a regionally alternate universe to nitpick the simplification of Lambda guv as a dark energy constant for purposes of a messageboard discussion.
quote:No I find it ignorant.
If you find my not finding that productive to be lacking in "civility"
There is a large problem in present day science. If there weren't, the North Pole would either be ice free, or the idiots and theorists predicting it to be ice-free by 2013 (perhaps you amongst them) would be called out. If there was not a major problem with 21st Century "science," UN propagandists like Guterres would be called out by every scientist on the planet.
Volcanic eruptions do not result in the Quaternary's cyclical 0.11Ma atmospheric CO2 peaks and troughs. SARS-CoV-2 did not originate from Bat Soup in the Hunan Wet Market. The CV19vax should never have been employed under EUA for general use in pediatrics. "Concern" rather than science drives that bullshite. Nitwits like yourself support it.
This post was edited on 9/27/23 at 11:57 am
Posted on 9/26/23 at 4:00 pm to Herooftheday
quote:
It's one thing to strike up a conversation, it's another to jump in in order to say someone is stupid and trolling, which I didn't deserve.
We were discussing speciation - creation of new species in a laboratory setting. You said something to the extent of “like a chimera?” I figured you were talking about the mythological beast with the head of a lion, tail of a dragon, and body of a goat. If you weren’t trolling, and if that was a legitimate question, then I highly recommend you refresh on the subject matter of high school biology and then read a modern book explaining evolution.
Here’s one example:
Amazon: “the Greatest Show on Earth”
Posted on 9/26/23 at 4:11 pm to Squirrelmeister
quote:
I figured you were talking about the mythological beast with the head of a lion, tail of a dragon, and body of a goat.
I had read briefly a while back about human-monkey chimeric embryos. There are definitely moral road blocks here.
quote:
If you weren’t trolling, and if that was a legitimate question
Shouldn't have assumed that. It is a mythological creature but this article described what these folks were doing as creating a Chimera.
quote:
I highly recommend you refresh on the subject matter
Same to you. If it's mumbo jumbo then that's fine. I only briefly looked into it. I assumed me using that word would steer the conversation so that maybe y'all knew something because I trust about half of what I read.
Posted on 9/26/23 at 6:10 pm to Bass Tiger
quote:
There’s no good evidence of true evolution, where one kind becomes something totally different than the original life form. There are many examples of species adaptations.
Give me irrefutable evidence of a life form that’s evolved from a primitive state, say like a single cell or even a sea creature that’s evolved to a more complex form of life where the steps of evolution are documented incrementally in some type of fossil records. You’re not gonna find it.
literally all you have to do is briefly glance at geologic history. What happened before the Cambrian Period? Why was there no life? What did early life in the geologic record look like? Did it become more complex?
This post was edited on 9/26/23 at 6:11 pm
Posted on 9/26/23 at 6:51 pm to NC_Tigah
quote:Nitwit? Whose "uncivil"? Jeez, buddy, hypocrisy much ? Listen, maybe you're right, maybe you're wrong. I give it 50/50 odds! But I don't care either way.
No nitwit, I'm now here to point out that your knowledge of the English language lags what you think you understand of it.
quote:
Volcanic eruptions do not result in the Quaternary's cyclical 0.11Ma atmospheric CO2 peaks and troughs. SARS-CoV-2 did not originate from Bat Soup in the Hunan Wet Market. The CV19vax should never have been employed under EUA for general use in pediatrics. "Concerns" rather than science drives that bull shite. Nitwits like yourself support it.
Volcanic eruptions + COVID ? Those aren't even remotely related. When you're ready to calm down and be taken seriously, try and limit the scope of what you wanna say to something in particular. I don't care about your general distrust of science. That's your problem.
Posted on 9/26/23 at 7:35 pm to Peebles
quote:You aren't really as perceptive a reader as I suspected. I tried to be civil, nitwit.
Whose "uncivil"?
"Tried" is past tense.
Past tense is a tense expressing an action which has happened or a state that previously existed. Lol..here, let me expand your understanding of the English language. Check out the past and past participle of verb #1 LINK
quote:Virtually never.
hypocrisy much ?
quote:Actually, yeah, they are. Science and scientific method is the tie-in each instance (I guess it's kind of like an IQ test. Some get the relationships, some don't). You are familiar with Science and the Scientific Method?
Those aren't even remotely related.
quote:and there it is. There is the "emotional" stuff you so vigorously defended in your Preprint.
When you're ready to calm down and be taken seriously,
---
FYI, I tossed out multiple topics, so you could take your pick. It was for your benefit.
I thought you might feel comfortable to try at least one.
Guess not.
FWIW, each is an example of "professional" "expert" scientists (as opposed to the armchair guys) acting stupidly. Each example is loaded with "professional" "experts" who are quite "concerned" about challenges to basically unsupportable hypotheses.
Hint: At this stage, if you do take one of these up, shy away from the CV19 topics, you'll embarrass yourself less defending the volcano/cowfart hypotheses.
Posted on 9/26/23 at 7:46 pm to NC_Tigah
Have the biblical flat earthers come in yet?
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