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Author | Topic: What's the Fabric of space made out of? | |||||||||||||||||||||||||||
Trae Member (Idle past 4306 days) Posts: 442 From: Fremont, CA, USA Joined: |
Time is the universe's 4th dimension If the 4th dimension is just a measurement, why isn’t the 3rd just a measurement? I think this discussion if continued would pull the thread off topic. Mainly I just tossed it out to see if it would give you a different way to think about space. If it doesn’t do that, that’s okay. Maybe someone else will have a comment that will help.
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Parasomnium Member Posts: 2224 Joined: |
Trae writes: I think this discussion if continued would pull the thread off topic. I don’t think that talking about time is off-topic for this thread. After all, ever since Einstein, the concensus in science is that space and time are intimately linked and known together as ‘space-time’. Talking about space without considering time is like taking a dip in a swimmingpool without water.
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RAZD Member (Idle past 1405 days) Posts: 20714 From: the other end of the sidewalk Joined: |
My warehouse takes up a finite measurable three dimensional spatial area. it also can only be measured between certain coordinates on the time line axis. before t=a there is no warehouse, and after time t=b there is no warehouse, so the warehouse has a time dimension of {b-a} we are limited in our ability to understand by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}
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JonF Member (Idle past 168 days) Posts: 6174 Joined: |
I think the question is, that if the absorption and emission of light is quantified by the energy levels of the electron orbits, then why is light more broad-band than the absorption bars? OK. The absorption and emission of light by changing energy levels from atoms and molecules and ions is quantized (not quantified) by the energy levels of the electron orbitals. The vast majority of the light emitted by the Sun is emitted by a plasma (I forget the name of the layer) in which the electrons have all been stripped from the nuclei, and there are no electron orbitals. It's just pure thermal emission. Acceleration of charged particles, like the nuclei and nucleons found in the plasma, produces electromagnetic radiation. The light is, of course, emitted in quanta (otherwise we'd be back at the ultraviolet catastrophe) but the wavelengths are not quantized. IT's very close to the famous "black body' emission curve: Incandescent bulbs are mostly pure thermal emission, but there's some energy-level stuff going on; that's why "sodium" street lights are distinctly yellow. The outer layer of the Sun isn't hot enough to be a plasma, or hot enough and dense enough to produce significant thermal radiation on its own. So we see its absorbtion bands in the light coming from deeper in the Sun. See Black Body Radiation and Applet: Blackbody Spectrum (requires Java).
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Buzsaw Inactive Member |
it also can only be measured between certain coordinates on the time line axis. before t=a there is no warehouse, and after time t=b there is no warehouse, so the warehouse has a time dimension of {b-a} Thanks Razd, for the cool physics 101 lesson. So I could've simply said:'My spacetime warehouse has a single time dimension and three finite spatial dimensions.' The immeasurable present is forever consuming the eternal future and extending the infinite past. buzsaw
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Buzsaw Inactive Member |
I'm sure we'll continue to answer questions and explain issues as best we can; and that we'll continue to point out that even better and more details answers can be found with the hard work of further study and lots of maths. Please understand that I do much appreciate the answers and work you've gone to to explain the issues. I'm aware that you've certainly gone to a whole lot more work and study on physics over the years than I who am a beginner/novice. Imo, it may be good for you higher physics buffs to have some logical problems brought forth from the street laity since you don't likely have to deal with some of these logic questions in the science arena. I have definitely learned much from your work and hope we can continue to dialog on the issues that come up. Thanks much! The immeasurable present is forever consuming the eternal future and extending the infinite past. buzsaw
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Loudmouth Inactive Member |
quote: I completely agree with your sentiment, Buzz. However, the layperson often confuses "logic" with "common sense". The two are not the same thing. Space/time, relativity, and a host of other things within physics defy common sense but they are logical. I think this is where you are running into problems, thinking that physics has to make "sense" instead of figuring out if the conclusions are consistent with the evidence.
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RAZD Member (Idle past 1405 days) Posts: 20714 From: the other end of the sidewalk Joined: |
it's a way of thinking about it. one of the things that comes out of subatomic experiments is that anti-particles behave as if they are moving in the other direction in time compared to a regular particle. you can think of an anti-electron as being an electron going back in time ...
we are limited in our ability to understand by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}
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RAZD Member (Idle past 1405 days) Posts: 20714 From: the other end of the sidewalk Joined: |
of course, and thanks. I was trying to clarify the question (the way it struck me) and the issues discussed so far (quantized light energy) with a seeming contradiction (broadband light).
we are limited in our ability to understand by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}
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JustinC Member (Idle past 4844 days) Posts: 624 From: Pittsburgh, PA, USA Joined: |
Thanks for the explanation. I've been reading a lot about black body radiation, so let me see if I have got this right.
The reason the frequency of light is quantized when emmitted from an atomic orbital is because the orbitals are quantized according to energy, and a release in that quantized energy produces a quantized photon using Planck's equation E=hv. When you have free moving charges, the black body curve is produced by the quantization of the emission and absorption of light. The free moving charges can produce any photon, but the charge must have enough energy to produce that particular photon. Since temperature is a measurement of the average kinetic energy of the particles, the probability of any deviation in kinetic energy for any one particle is inversely proportional to the deviation. To produce a photon of very high frequency, the electron must have a large kinetic energy and the probability of this is proportional to its deviation from the average kinetic energy. This is why the black body curve drops off at higher frequencies. So in a dense ball of charged particles, the energy is going to be distributed according to the average kinetic energy, but it will be continuously distributed and hence there will be a continuous spectrum. Inside an atom, there isn't a continuous distribution of energy, it is quantized, and thus the spectrum is quantized. Does this sound accurate?
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JonF Member (Idle past 168 days) Posts: 6174 Joined: |
Yup, that's a pretty good summary.
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Buzsaw Inactive Member |
I think this is where you are running into problems, thinking that physics has to make "sense" instead of figuring out if the conclusions are consistent with the evidence. Mmm....then nonsense is cool with physics? Seriously, imo, the problem with too little regard for both common sense and logic is that these babys sometimes get thrown out with the bathwater in assessing claimed evidence. With that in mind, would you consider my Message 63 to Sylas as a logical proposition or a common sense proposition/problem? I'd be interested to see what you and others here would have for a response to Message 63.
Changed "message 63" to "[msg=-63]", which actually takes one less character - try it, you'll like it! --Admin This message has been edited by Admin, 03-12-2005 13:12 AM The immeasurable present is forever consuming the eternal future and extending the infinite past. buzsaw
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sidelined Member (Idle past 5908 days) Posts: 3435 From: Edmonton Alberta Canada Joined: |
buzsaw
Do you have Real Player installed on your computer? If so, how about checking out this site to get a taste of the problem facing common sense when dealing with world we live in? Page Redirection Enjoy!
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NosyNed Member Posts: 8996 From: Canada Joined: |
Mmm....then nonsense is cool with physics? Seriously, imo, the problem with too little regard for both common sense and logic is that these babys sometimes get thrown out with the bathwater in assessing claimed evidence. I recommend you listen to the first lecture Buz. At between 20 minutes and 26ish minutes he points out the the professors don't understand this stuff. He says "You'll have to accept it. ... That is the way it works...If you don't like it go somewhere else -- to another universe where the rules are simpler." Feynman is talking to you Buz. This, that you call nonsense, is the way the universe IS! You're the one who thinks God made it. Take your issues up with Him; it is all His idea. This message has been edited by NosyNed, 03-12-2005 01:39 AM
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Percy Member Posts: 22392 From: New Hampshire Joined: Member Rating: 5.3 |
I concur with Nosy's recommendation to listen to the first lecture from the 20 minute mark to the 26 minute mark. If you listen to nothing else, at least listen to that much, here's the link: http://vegaserver1.hpc.susx.ac.uk:8080/...eynman/feynman1.rm
From your Message 63:
My argument implicates that alleged curvature and expansion of space is being assumed relative to specified bounded areas of it being studied or relative to the area of space, in which things like light, gravity, et al exist. The better theory is the one that more closely describes what is actually observed. Perhaps someone can think of tests that would differentiate between your model and the one currently accepted within science. --Percy
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