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jgill
Boulder climber
Colorado
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Sep 11, 2014 - 12:15pm PT
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Thank you, Ed. Excellent posts!
;>)
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High Fructose Corn Spirit
Gym climber
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Sep 11, 2014 - 12:25pm PT
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Yes, Ed, excellent posts.
Fair enough, I've carried on long enough anyways.
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BLUEBLOCR
Social climber
joshua tree
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Sep 11, 2014 - 01:17pm PT
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These posts are GREAT! I'll h e to catch up later gotta work. You know causality.
PEASE can anyone describe in laymans terms;
How does electricity run through a wire? What does it actually look like??
Thank you!
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Ed Hartouni
Trad climber
Livermore, CA
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Sep 11, 2014 - 02:22pm PT
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if you ask about the fundamentals of the universe you are asking questions about high energy physics... now many of those fundamentals generalize and contribute to or take contributions from other areas of physics.
I'm not smart enough to grasp all of these things, and besides, I'm an experimentalist and so I revel in the details, not the generalities...
There is a fundamental rule that governs the entire universe: Causes happen before effects and not the other way around.
you have to deal with an issue, regarding causality, from a quantum mechanical point of view where you have made it a relativistic theory that running time forwards and backwards gives you physically reasonable results.
So our electron A emits a photon that goes off and hits another electron B... we have a clear sense of the causal order...
however, there is also the equivalent process that when we run time backward that positron B emits a photon that hits positron A, the causal order is reversed, but the two scenarios are equivalent, they are, in fact, identical.
All sorts of things happen in that transformation, which is a fundamental symmetry of the universe (which is not time reversal alone, however).
The two situations are causal, but the sequence of the causation has been reversed.
To modify your statement to make it consistent with known symmetries (not just known, but measured) you have to allow for the fact that you can reverse the process too...
That gets you to physics in the 1920s...
(though the simplifying examples took a long time to develop).
if we went out climbing together and you asked a particular question you might just get an answer from particle physics...
by the way, quantum mechanics is the foundation of our scientific knowledge of how the universe works and is not just a topic in particle physics... but it is a thing particle physicists know well, especially its extension to the relativistic domain.
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High Fructose Corn Spirit
Gym climber
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Sep 11, 2014 - 02:29pm PT
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There is a fundamental rule that governs the entire universe: Causes happen before effects and not the other way around.
Well, Ed, that's a Stephen Hawking (physicist) quote word for word. It's not mine. Thanks for responding to it.
I wanted to see how you, personally, would handle it.
It's a statement, a Hawking statement, that makes sense to me. Just as it stands. However, maybe I'm missing something. (In addition to "glossing" over something?)
by the way, quantum mechanics is the foundation of our scientific knowledge of how the universe works and is not just a topic in particle physics...
Of course. It's also the basis of all chemistry and biology if you want to draw it out. All I'm saying is that it brings a great deal of order with it in a constrained, determinant sort of way - the "order" of which appears to be "obedient to" cause n effect, through and through, top to bottom.
Anyways thanks for the reply and the conversation, I've had my fill for awhile.
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Tvash
climber
Seattle
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Sep 11, 2014 - 02:45pm PT
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I had dinner with a friend last night, and she told me she just had a physicist as a house guest for the previous week. I mentioned that I'd been reading some physics articles lately by a guy named Strassler.
Guess who her guest was?
The universe is, indeed, strange.
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jstan
climber
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Sep 11, 2014 - 03:08pm PT
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I think Ed's point was that for whatever the reason antimatter lost out to equal amounts of matter after the Big Bang, had the contest gone the other way you would understand causality entirely differently; and it all comes from the same theory. A theory that has worked distressingly well since about 1870.
It has distressed us because, among other things, we are made of matter. To get an idea of how Feynman found this just as unsettling as do the rest of us, Google "Feynman Robb Memorial Lectures". Based upon your respect for superb pedagogy I expect you will enjoy these four lectures immensely.
As I understand it Bohr voiced an answer to many such questions when his advice to doubters was reportedly, "Shut up and calculate."
This may be the picture you seek.
http://profmattstrassler.com/about/about-me/
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WBraun
climber
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Sep 11, 2014 - 03:28pm PT
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we are made of matter.
No we are not.
And that IS the illusion!
The gross materialists are stuck in the deep trough of Aristotelian/Cartesian logic,
where something can either be true, or false, but not both.
Where as in non-Aristotelian logic we can have situations where multiple truth values hold simultaneously.
Something can be non-dual and separate simultaneously, etc.
Achintya-bhedabheda-tattva simultaneous oneness and difference.
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Tvash
climber
Seattle
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Sep 11, 2014 - 03:41pm PT
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We're made of meat.
Perhaps you might email Strassler himself for story verification, HFCS. FYI, the storyteller's initials are MF.
While you're at it, you might actually read some of his posts. They're pretty good.
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Tvash
climber
Seattle
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Sep 11, 2014 - 04:31pm PT
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For you 'stuff and thingists' out there:
A bit of Strassler I found illucidating, particularly with regards to the oft oversimplified and misinterpreted E=Mc2 equation. I know this is Cosmology 101 stuff, but still:
"Einstein and his followers established that for any ordinary object, the relation between its energy E, momentum p and mass M [sometimes called ``rest mass'', but just called `mass' by particle physicists] is
E2 = (p c)2 + (M c2)2
For a slow-moving object, p ≈ Mv (where v is the object’s velocity) and pc ≈ Mvc is much smaller than Mc2. And therefore
E2 ≈ (M c2)2 (i.e., E ≈ M c2 for slow objects)
Since planets, moons, and artificial satellites all move with velocities well below 0.1% of c relative to each other and to the sun, the gravitational forces between them are proportional to
E1 E2 ≈ M1 M2 c4
And since c is a constant, for such objects Einstein’s law of gravity and Newton’s law of gravity are completely consistent; the force law is proportional to the product of the energies and to the product of the masses, because the two are proportional to one another.
But for objects that have high speeds relative to one another, or for objects subject to extremely strong gravitational pulls (which will quickly develop high speeds if they don’t have them already), the Einsteinian law of gravity involves a complicated combination of momentum and energy, in which mass does not explicitly appear. This is why Einstein’s version of gravity even pulls on things like light, which is made from photons that have no mass at all. (And it is why gravitational waves — waves in space and time, massless just like light — can be formed by objects that are orbiting one another.) Simply put, the Einsteinian view of gravity (now reasonably well confirmed by experiment) differs significantly from the Newtonian view, and in particular, it is not mass but energy and momentum which are primary. And all objects, not matter what they are made from or how they are moving from your point of view, have energy — so everything in the universe exerts a gravitational effect on everything else. We say “gravity is a universal force ”(here the term is not referring not to the universe but to the notion of universality — of complete generality.)"
http://profmattstrassler.com/articles-and-posts/the-higgs-particle/the-higgs-faq-2-0/
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Tvash
climber
Seattle
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Sep 11, 2014 - 04:40pm PT
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More about Stuff and Things from same link:
"Other things get their masses from sources other than the Higgs field. The majority of the mass of an atom is its nucleus, not its lightweight electrons on the outside. And nuclei are made from protons and neutrons — bags of imprisoned or “confined” quarks, antiquarks and gluons. These quarks, antiquarks and gluons go roaring around inside their little prison at very high speeds, and the masses of the proton and neutron are as much due to those energies, and to the energy that is needed to trap the quarks etc. inside the bag, as it is due to the masses of the quarks and antiquarks contained within the bag. So the proton’s and neutron’s masses do not come predominantly from the Higgs field. [Experts: There is a subtlety here, having to do with how the Higgs field affects the confinement scale; but even when it is accounted for, the statement remains essentially true.] So the mass of the earth, or the mass of the sun, would change, but not enormously, if there were no Higgs field… assuming they could hold together at all, which would not be true of the earth.
And black holes, which are some of the most massive objects in the universe, holding court at the centers of most galaxies, can in principle be made entirely from massless things. You can make a black hole entirely out of photons, in principle. In practise most black holes are made from ordinary matter, but ordinary matter’s mass is mostly from atomic nuclei, and as we just noted, that doesn’t come entirely from the Higgs field.
No matter how you view it, the Higgs field is not the universal giver of mass to things in the universe: not to ordinary atomic matter, not to dark matter, not to black holes. To most known fundamental particles, yes — and it is crucial in ensuring that atoms exist at all. But there would be just as much interesting gravitational physics going on in the universe if there were no Higgs field. There just wouldn’t be any atoms, or any people to study them."
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High Fructose Corn Spirit
Gym climber
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Sep 11, 2014 - 05:02pm PT
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So I prick my finger and feel pain in my mental life. In my mental life, the pain I feel is a thing. But what if... outside of that, my pain isn't a "thing" at all.
[Click to View YouTube Video]
Nicholas Humphrey, philosophically thoughtful psychologist, on "Is Consciousness an Illusion?"
Seemed relevant to the thread. A thing in one frame but no thing in another. :)
Also a warning: this evolutionary psychologist speaks of nature "designing" us. (Say what?!!)
http://www.youtube.com/watch?v=NHXCi6yZ-eA
It might be semantics here to a degree, but if consciousness is an illusion, Harris needs to make way, lol!
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jstan
climber
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Sep 11, 2014 - 05:04pm PT
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We have got him Guys! He isn't going to get away.
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WBraun
climber
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Sep 11, 2014 - 06:03pm PT
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So? What does any of that have to do with mind woo?
It's become Fruit's religion hysteria thread.
Aaaacckkk !!!!! the Abrahamic zombie apocalypse
HFCS says I must destroy these zombies .....
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Tvash
climber
Seattle
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Sep 11, 2014 - 06:13pm PT
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I just think it's interesting how unsubstantial 'stuff' really is, as far as we know.
It's also interesting that you can make a black hole out of nothing but photons. I'm gathering a bunch already.
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MikeL
Social climber
Seattle, WA
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Sep 11, 2014 - 06:57pm PT
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HFCS: I wanted to see how you, personally, would handle it.
This make you a troll (perverse, inauthentic, dishonest).
Linda Hill studies political conflict at Harvard. She has written that it's easy to mistake another's lack of competence for poor character. With you, I'd say it might be the other way around.
Tvash: . . . it's interesting how unsubstantial 'stuff' really is, as far as we know
+1
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Tvash
climber
Seattle
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Sep 11, 2014 - 07:44pm PT
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I've had the pleasure of being a master debater in a number of public forums. Usually, I go out for drinks with my opponents afterwards, and have have a good time with them.
One notable exception was when I went up against the former Deputy CIA director under Reagan in front of a fairly well educated San Juan Island County (lots of retired PhDs out there) audience. The broader topic was the loss of civil liberties post 911. As invariably happens, we got on the topic of 'terrorism', which, he made clear, was synonymous with 'Muslims'.
He had just recently published a book and spent a good deal of his limited time working through it's talking points - the main one being his brilliant (in his own mind, anyway) analogy that, while we all operated on the same 'hardware' - Muslims used a different 'operating system' - which they sought to impose on Americans.
Well, suffice to say, it was a target rich environment as far as I was concerned. Frankly, I expected a lot more from a man with his credentials.
He made two beginners mistakes. One - he got visibly angry, personal, and disrespectful - something that never plays well with a general audience, particularly an educated one. Two - lacking viable rebuttals, he trotted out his credentials in lieu of any real counterpoints or new arguments.
It was clear from the audience feedback during and after that I succeeded in politely tearing his dehumanizing thesis - such as it was, a new rhetorical as#@&%e. He didn't appear to be accustomed to being challenged, much less by a nobody from a what was then an obscure advocacy group in Seattle.
I'll never have the training needed to be fluent in the mathematical language of particle physics, but I do have enough math training to internalize some or most of what Ed, Strassler, and others post for general consumption. This never fails to extend my understanding of the fundamental workings of the universe, such as we currently know them.
For example, I've been fairly in the dark with regards to the basic principles of the standard model. More importantly, I was completely in the dark with regards to the general relativity's treatment of gravity for high speed phenomena like photons - most notably that energy and momentum, not mass, determines gravitational behavior there.
Now we're tiptoeing into our understanding the Higgs field (or fields?), which at least gives us an indication of what Dark Matter isn't, as well as fleshing out a richer story of the Big Bang. I have some understanding of the profound significance there now - as well as the limitations of that significance.
These were 'dark' areas for me previously, so it's kind of a cool thing to shed a little light on, as well as lose one's intellectual fear of.
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BLUEBLOCR
Social climber
joshua tree
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Sep 11, 2014 - 07:54pm PT
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Nice Tvash!
[sometimes called ``rest mass'', but just called `mass' by particle physicists]
Did it say what qualified as "mass"? i get that "mass" is the combination of matter and energy. So would 1 atom of matter have mass?
the Einsteinian law of gravity involves a complicated combination of momentum and energy, in which mass does not explicitly appear. This is why Einstein’s version of gravity even pulls on things like light, which is made from photons that have no mass at all.
DMT-did you read this?
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