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Why are Stars Star-Shaped? - Minute Physics

siftbot says...

Tags for this video have been changed from 'stars, star shape, minute physics' to 'stars, star shape, minute physics, suture lines, eye, diffraction, fourier transform' - edited by Eklek

transtitions in the holographic universe

Chairman_woo says...

^ You can make all of that make sense by simply shifting your epistemological position to the only ones which truly make sense i.e. phenomenology &/or perspectivism.

To rephrase that in less impenetrable terms:
"Materialism" (or in your case I assume "Scientific Materialism") that is to say 'matter is primary', from a philosophers POV is a deeply flawed assumption. Flawed because there appears to be not one experience in human history that did not occur entirely within the mind.
When one see's say a Dog, one only ever experiences the images and sensations occurring within ones mind. You don't see the photons hitting your retina, only the way your mind as interpreted the data.

However the opposite position "Idealism" (mind is primary) is also fundamentally flawed in the exact opposite way. If our minds are the only "real" things then where exactly are they? And how do we even derive logic and reason if there is not something outside of ourselves which it describes? etc. etc.

Philosophers like Husserl, Heidegger and Sartre' got around this by defining a new category, "phenomena". We know for certain that "phenomena" exist in some sense because we experience them, the categories of mind and matter then become secondary properties, both only existing as definitions we apply retrospectively to experiences. i.e. stuff happens and then our brains kick in and say "that happened because of X because in the past X has preceded similar experiences" or "that thing looks like other examples of Y so is probably Y".

The problem then is that this appears to come no closer to telling us what is objectively happening in the universe, it's more like linguistic/logical housekeeping. The phenomenologists and existentialists did a superb job of clearing away all of the old invalid baggage about how we try to describe things, but they did little or nothing to solve the problem of Kants "nouminal world" (i.e. the "real" stuff that we are experiencing by simulation in our minds).

Its stumped philosophers for centuries as we don't appear to have any way to ever get at this "nouminal" or "real" world we naturally assume must exist in some way. But....

I reckon ultimately one of the first western philosophers in history nailed the way out 3000 or so years ago. Pythagoras said "all is number" and due to the work of Euler, Riemann and Fourier in particular I think we can now make it stick. (yeh its turning into an essay sorry )

Without wishing to go deep into a subject you could spend half your life on; Fourier transforms are involved in signal processing. It is a mathematical means by which spatio-temporal signals (e.g. the vibration of a string or the movement of a record needle) can be converted with no meaningful loss of information into frequency (analog) or binary (digital) forms and back again.

Mathematically speaking there is no reason to regard the "signal" as any less "real" whether it is in frequency form or spatio-temporal form. It is the same "signal", it can be converted 100% either direction.

So then here's the biggie: Is there any reason why we could not regard instrumental mathematical numbers and operations (i.e. the stuff we write down and practice as "mathematics") and the phenomena in the universe they appear to describe. I.e. when we use man made mathematical equations to describe and model the behavior of "phenomena" we experience like say Physicists do, could we suggest that we are using a form of Fourier transform? And moreover that this indicates an Ontological (existing objectively outside of yourself) aspect to the mathematical "signals".

Or to put it another way, is mathematics itself really real?

The Reimann sphere and Eulers formula provide a mathematical basis to describe the entirety of known existence in purely mathematical terms, but they indicate that pure ontological mathematics itself is more primary than anything we ever experience. It suggests infact that we ourselves are ultimately reducible to Ontological mathematical phenomena (what Leibniz called "Monads").

What we think of as "reality" could then perhaps be regarded as non dimensional (enfolded) mathematics interacting in such a way as to create the experience of a dimensional (unfolded) universe of extension (such as ours).

(R = distance between two points)
Enfolded universe: R=0
Unfolded universe: R>0

Neither is more "real", they are simply different perspectives from which Ontological mathematics can observe itself.

"Reality": R>=0

I've explained parts of that poorly sorry. Its an immense subject and can be tackedled from many different (often completely incompatible) paradigms. I hope at the very lest I have perhaps demonstrated that the Holographic universe theory could have legs if we combine the advances of scientific exploration (i.e. study of matter) with those of Philosophy and neuroscience (i.e. study of mind & reason itself). The latest big theory doing the rounds with neuroscience is that the mind/consciousness is a fractal phenomenon, which plays into what I've been discussing here more than you might think.

Then again maybe you just wrote me off as a crackpot within the first few lines "lawl" etc..

Quantum Teleportation

soulmonarch says...

>> ^messenger:

...I thought that it was an absolute fact that you cannot determine both the speed/direction and position of anything, no matter how it's measured by definition of the measurement of speed/direction requiring more than one position. That's to say, I'm under the impression that the Heisenberg Uncertainty Principle has nothing to do with technology and will always be true under any conditions with any equipment in the areas where it applies, world without end, Amen. Am I wrong?


That is a combined 'yes' and 'no' answer.

Yes: Measuring exact values of electron is really hard. They don't even show up as precise values when we look at them, simply because they are so small and move so fast. We see that as a sort of 'smear'. (A Fourier transform.)

Heisenberg's equations for determining more precise values don't commute. (i.e. You cannot shuffle the variables around and still have it work.) This implies that it should be mathematically impossible to determine the velocity and position at the same instant.

No: Because all of the above is still based on the assumption that that our current method of measuring particles is all there is. If they could be measured more accurately or without adding energy to the system, the Uncertainty Principle should no longer be relevant.

Of course, science is pretty sure that's impossible. (Hell, they didn't even have that in Star Trek.) But we've proved ourselves wrong a lot of times in the past.

Gorgeous animation of Auditory Transduction

SwimWithSharks says...

>> ^grinter:

>> ^charliem:
So what hes saying is that our ear does a physical Fourier transform on the auditory signals its receiving.......cool!

Well, yes! The tonotopic mapping of the cochlea is kindof like that. When you start considering all of the other signal processing 'tricks' the auditory system uses (frequency dependent filtering, neural integration on spacial and temporal scales, otoacoustic emissions, etc) it gets way cooler! I just wish I could find an animation for those.


not sure about animation, but vihart's video goes into more detail on this

http://videosift.com/video/Vi-Hart-What-is-up-with-Noises

it makes for a good follow-up

Gorgeous animation of Auditory Transduction

grinter says...

>> ^charliem:

So what hes saying is that our ear does a physical Fourier transform on the auditory signals its receiving.......cool!

Well, yes! The tonotopic mapping of the cochlea is kindof like that. When you start considering all of the other signal processing 'tricks' the auditory system uses (frequency dependent filtering, neural integration on spacial and temporal scales, otoacoustic emissions, etc) it gets way cooler! I just wish I could find an animation for those.

Gorgeous animation of Auditory Transduction

The most amazing photo ever taken

StukaFox says...

Amazingly, NASA took the famous deep field photo and passed it through a signal analyzer consisting of 200,000 quad-core CPU's in a Beowulf cluster running a stripped down version of Redhat's RHEL. For roughly 10^29 iterations, these processors ran an optimized fast Fourier transform on the collected data until a pure signal was collected. That signal, a complex series of interlocking sign waves, was then passed through the cluster again, the researchers were totally shocked by the result. A single, simple message, broadcast by the universe its self, to the human race:

"Sarah Palin's a cunt."

Science is truly, truly amazing.

Husky says "I love you"

13439 says...

That is NOT "I love you."

It's "I'm hungry."

I know this because dogs say only five things:
"Hey"

"I'm hungry"

"I gotta go! I REALLY gotta go!"

"I just ate something that I found on the lawn. Now come here so I can lick you all over your face."

and, occasionally,

"Einstein was a pretty smart guy there, but he missed a Fourier transform in step 23 of his proof that would if exploited actually have achieved a possible vector toward the Grand Unified Theory of the Universe. Too bad, really. Oh, and his hair makes him look like a poodle on crack."

dystopianfuturetoday (Member Profile)

fizziks says...

Ok, so I have to admit, I was really confused for awhile when people on the sift kept mentioning "DFT this" and "DFT that" since I thought they meant Discrete Fourier Transform.

I guess I've been Sifty-ized since I now know they're talking about you...

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