Any Amateur Astrophysicists?


#21

Yeah I can totally imagine the local Eastender’s lasses asking their mates to shut up for a minute so that they can play what sounds like a dial-up sequence of a 1990s modem so they can record it an upload their new selfie haha


#22

No, I’m being thick. You could simply do it internally and run it through a convolver and then produce the image?

It’s a funny thought though


#23

Ever heard of Dr. Rupert Till?
He’s a DJ, acoustics engineer, and archaeoacoustic archaeologist.
He did some pretty impressive work on studying the architectual design of Stonehenge from the perspective of acoustic properties.
The results are rather interesting. If you look at it, from this angle of thought, even the visual design of it (if you’re looking at the top) almost immediately leaps out as a concert venue design.

Look at the inner stones (the “blue stones”), easily spotted because they are the small stones that don’t form a circle. Look at that shape, and then consider the shape we use for a concert hall or the engineering area of a studio.

Dr. Till wrote about the acoustical properties at pretty sizable length over a few years, and made a few videos that were quite fascinating (which appear to have all died the way of “old stuff on the web” unfortunately).

Here’s one of his writings on academia.edu.

Cheers,
Jayson


#24

Wow, that’s quite interesting. I can definitely see the concert hall resemblance.

I’d love to shout at Stonehenge - not every day that sentence actually makes sense.

I’ll have a read of that - not tonight as that’ll just stimulate my mind and I won’t be able to sleep!

Thanks for the link!


#25

Also cool, by the way, and lost to one of the videos that died the way of old things on the internet, is that Till found that if you have torches on the outer stone circle walls where it appears they had such set, and you play a drum pattern that is synchronized with the acoustical feedback of the area (the beat’s reverb - if you hit a certain beat, then the mixing between the beat and the reverb return actually becomes a pulsing hum), then the torches actually get suffocated of air for a moment and then they grab air again, etc… from the pressure waves…basically, you end up with a strobe effect. lol

Wish I could find the damn video.

Cheers,
Jayson


#26

Yay! I found the old history channel (when it was an actual history channel) documentary Dr. Till did on the subject - it has lots of good bits.

(note to self - combine these, save to my cloud…pain in the ass to find)

Cheers,
Jayson


#27

What do you guys think about the Holographic Principle, and the hypothesis that the universe is a hologram?

Some really interesting stuff on a high level but I can’t quite wrap my mind around the entirety of it.


#28

I generally find those concepts “meh”.
It falls only slightly more worth consideration to me than investigating the claim that there’s an invisible tea saucer in orbit around CW Leonis that accounts for a portion of CW Leonis’ rotational behavior.

Cheers,
Jayson


#29

The universe isn’t a hologram. From what I understand, it’s more of a mathematical tool that allows us to solve the problem of understanding gravity in the quantum realm.

If you were to add the smallest possible quantity of energy into a black hole, it’s surface area increases by 1 square planck length. So, the surface area of the event horizon is proportional to the its mass.

Apparently that lead to the idea of the holographic principle.

Understanding it in three dimensions causes the mathematics to produce infinity, and nobody has any idea of how to solve that. But, when the three-dimensional information is encoded onto a 2-dimensional surface, the issue goes away.

So, they can translate a 3-dimensional representation into a 2-dimensional representation, and perform some calculations, and then translate it back to three-dimensions again.

Disclaimer: I’m not claiming to understand the mathematics! But I did look into the surface layer of the subject when all of those news stories appeared and overblew it entirely for drama.

It is theoretical physics, and subject to change, so it may just be one possible interpretation or tool that isn’t correct.


#30

That’s interesting! Thanks for the response. This is the article that kind of lead me to thinking about it.

All based around qubits and entanglement.


#31

Yeah, my opinion on that has always been to point out that any employment of general relativity is translated down into a 2 dimensional model.

No one employs it in its native structure of 3 dimensions plus time.
It’s always 2 spacial dimensions plus time. That is, linearized. Always.

If you ask the smartest physicists on the planet to find an exact non-linearized solution of general relativity, they’ll laugh.
No one has ever resolved a non-linearized exact solution for general relativity…ever.

Every prediction, stretching back to the famous solar eclipse proof, was done by employing a linearized approach.

When they recently calculated gravitational waves to build the lab and test the results of detecting gravitational waves from black hole collisions, the entire model was a linearized model; not a 3 dimensional model.

So…the idea that something runs off into infinity when you try to operate it in 3 dimensions regarding a black hole, which is a mathematical product of general relativity in terms of the equations used to describe them, it’s not at all surprising to me.

To me, that’s a bit of a…“Well…no shit. You can’t even solve general relativity in 3 dimensions, so what hope did you have of its most extreme portion, which itself in general relatively runs off into infinity, NOT producing a result of running off into infinity in 3 dimensions”?

Cheers,
Jayson


#32

@Jayson, I see, thank you for the extra detail.

@nostromer, I think perhaps a way of seeing it is, for all intents and purposes, the third dimension is actually encoded onto a 2-dimensional surface, but it’s still three dimension, in a more abstract sense. The information is still there. So it doesn’t actually matter anyway.

I think it can be compared to the uncertainty principle, from which emerges the idea that any particle can be in any number of possible states before you observe it and its “wave function” collapses. That is, we’ve taken a measurement, and we now know where it is, where as before we measure it, all we had was a representation of the probability of the state it will be observed in.

So, for all intents and purposes, that particle is in all places simultaneously until it is observed.

That is not the say the particle knows when it is being watched, “observed” is a bad choice of word. But, the act of observation entails the interaction with the particle, therefore it’s state at that point in time is known.

But, of course the particle is actually there, but the idea that is possibly isn’t is an emergent property of the physics required to understand it.

And one could argue that it really is that way, because there’s no way to actually know for sure.

It essentially falls under the category of: not provable.


#33

Ah, I never thought of this being attributable to (for lack of a better term) the double-slit experiment. I always found it highly curious that subatomic particles behave as waves of probability when not observed.

The holographic principle is definitely not provable. Similar to say, trying to prove the 10th dimension. It’s all abstraction based on hypotheses that themselves are unprovable due to the limitations of our observation.


#34

Yeah, with the double slit experiment, the photon only behaves like a particle and a wave depending on how you look at it.

If you fire one photon at a time though a double slit, and record the photon reflected off of the surface behind, and then at the end, overlay all of the recorded reflections, you see bands of interference, as it the particle interfered with itself.

But fring one photon still only results a single photon being reflected from a point that is definite AFTER it was reflected.


#35

In regards to the uncertainty principle, there’s a lot of mythmaking that’s happened over the last half century regarding it, and @psyber is exactly right to point out the bottom line of that principle; that it’s a convention, not a reality.

Before the 80’s Paul Dirac’s textbook on Quantum Mechanics was a required text, but it was dropped starting in the 60’s around the same time that the Copenhagen Interpretation started to become damn near deified, which is only now starting to take cracks in that absolute position. After the 60’s if you questioned the Copenhagen Interpretation, then you were in jeopardy of heresy.

When it comes to the uncertainty principle, I like to highlight Heisenberg himself regarding that notion because I think it speaks volumes about how to go about understanding it.
(I think you’ll have to click and download to see it right…)

Actually, I wrote a whole article on it, showing how the mystery of the evaporation of time at the photon, and how the uncertainty principle in general, given the foundations of Heisenberg and Durac do not produce “strange” results, but results that actually make a LOT of damn good sense.

It’s thick at 10 pages, but I think that after you read it, you end up with a better comprehension of the principle’s context and implications.

Cheers,
Jayson


#36

Actually, I think they dis-proved that recently (along with string theory since it relies on higher dimensions).

Basically, one of the theories for why gravity is weak relative to other fundamental forces is that it travels through more than 3 dimensions plus time. That’s something we couldn’t test until we could measure gravity on a very large scale, but now that we have, we can.

So the gist of the study goes that light travels through 3 dimensions plus time and light decreases in intensity with the square of the distance it travels. Gravity, if it has to travel through higher dimensions, should decrease in intensity even more exponentially over really long distances, we’re talking an extra power of decay for every extra dimension gravity has to travel through. So, since we were able to measure and observe the gravitational waves from a known event a known distance from us of a known magnitude, we could calculate how “large” those waves would be at the source and look at the manner of their decay on their way to us. Turns out the numbers lined up very well with a 3 dimensions plus time framework.


#37

Oh did they? Interesting!! I always found the “exploring the 10th dimension” presentation to be an interesting one, albeit very far fetched.

So when you say plus time framework are you referring to it as the 4th dimension, or are you saying evidence now exists that there is in theory only 3 dimensions with a framework of time being a fundamental component within 3 dimensional space?


#38

I used to have a note hanging at my desk in bold letters that read,

“IF STRING THEORY IS CORRECT THAT GRAVITY IS ARRIVING TO US FROM AN EXTRA DIMENSION WHERE IT ORIGINATES, IS THEREFORE WEAKER BY THE TIME IT ARRIVES HERE, AND IF GRAVITY PROPAGATES AS A WAVE, THEN WHY ISN’T THE MOON VIBRATING EVER-SO-SLIGHTLY IN ITS ORBIT?”

It’s basically the idea of a long pole. If you mount the pole at one end, and give it a motor at the base to shake it so that it swings back and forth as a wave propagation of energy along the length of the pole, then the strength of that energy will be lesser at the end of the pole than at the base, but the end of that pole will have a wider range of physical motion in its oscillation than down at the mount because any wave propagation is less stable the farther it gets from the source…the waves stretch and widen.

Following that basic logic along the idea of gravity coming from extra dimensions…shouldn’t we be able to measure a vibration in our gravity that indicates such a transmission of wave energy?

But we don’t observe such a thing. Gravity isn’t unstable and wobbly. It’s among the more extremely reliable forces out there.

Cheers,
Jayson


#39

That, I’m not sure how to answer. Time trips me up because if you take it literally it’s simple, but when you start to think about the impact we let time have on various things and how wibbly wobbly it is relative to your speed…

For me, I work in finance, so we let time tell us some very interesting things about money in terms of interest and the time value of money and yields of various investments over time. The time value of money is the idea that having a dollar today is worth more than if I give you the same exact dollar tomorrow. Even taking inflation out of the picture, you could invest that dollar, earn a day’s worth of interest, spend it tomorrow and pocket the interest. That’s the basis of coming up with valuations like stock and bond prices. If we look at our best guess of how much money an investment will pay us and when it will pay us, then we can come up with a number, in dollars, that that investment is worth today, right now. If we can buy that investment for less than this “net present value”, then we can basically score some free money, assuming we make correct guesses about future payouts. And a lot of people have done this for a very long time and it usually works.

This also carries into economics and whether people know it or not, they’re using this principle to make decisions about money all the time. For instance, the yield curve for bonds just inverted so that a 10 year bond currently pays less than a 5 year bond, which is unusual because investors want more money the longer they have to wait for it as it presents a larger risk. The inversion usually precedes a recession by a year or so. What people are saying, without knowing it, is that they feel that 3-5 years from now is going to be a riskier, financially messier time than 10 years from now and they’d rather have their money locked away earning lesser returns at that time than try and put it into the market and hope for the same results. In other words, financial data can mirror human sentiment over time (which is part of how economics does its magic).

This stuff is just the tip of the iceberg when it comes to time and money, but I explain all this so that you can get where I’m coming from when I say that there’s no fundamental element so clearly defined (not even gold, which currency was more or less based upon for thousands of years), no rule of space, no rule of speed for money like that. The only fundamental physical anything that we tie to money this tightly, build our whole modern concept of accountancy and finance around, is time. I don’t know what that makes time, but that makes it something very interesting, whether nothing more than a human abstraction, a 4th dimension, or some other fundamental physical system. Because I think you see time very tightly linked with a lot of human constructs, things like sports, science, art (music itself is an art only over time, it doesn’t work without it). So I find it very difficult to comprehend time on its own and answer that question.


#40

This is something I actually have studied pretty extensively.

Time is a function. It’s doesn’t have an independent existence outside of being a function for quantification.

In physics, there’s a need to track a relationship between two states, so you have reference frame A and reference frame B. Two observations.
(A) was at position X1, Y1, Z1 and (B) was at position X2, Y2, Z2.

Now, if the object in inquiry is the same object in both reference frames, then we’re looking at an object moving over distance, or through space - both are ways of saying the same thing.

There isn’t actually a property of time.
What you have, in all reality, is a series of positions that are NOT infinite. They are not infinite because we know for a fact that nothing is smaller than the Planck scale, so, given enough instruments (and by that, I mean far beyond the count of quadrillions) we COULD outline the entire sequence of movement of the object from (A) to (B) by noting EVERY Planck length position it was in over the path.

Then we could operate our math over each and work out its velocity, for example, without bothering with a quantity of “time”. We would simply need to know the quantity of space, relative to the quantity of space that a photon also traveled. In so doing, we would then know the relative velocity of the object under observation.

HOWEVER, that is an INSANE set of operations just to get velocity, and one that is WAY over convoluted.
Time is a function that allows us to say, “Take these parameters and step them forward this many times in sequence, granting the assumption that any one sequence frame occurs by index subsequent to the sequence frame in the series preceding it.”

It’s not an actual thing or real dimension that you can find a boson resting in.
You can actually see this by looking at our previous conversation about the uncertainty principle.
Part of the discussion of the uncertainty principle routes around to the size of the scale we’re looking at, and that means examining exactly what we’re looking at for the Planck scale.

Well, one thing about the Planck scale, which is the smallest available amount of information/energy transferable, is that when you look at a photon and a Planck length, you see time collapse to equal a 1:1 relationship with distance.

Once you extrapolate the concept that when we employ Time, we’re basically employing a form of a Zip file so that we don’t have to do quadrillions of reference frame comparisons just to measure movement over a few centimeters, you quickly start to arrive at a position that time doesn’t evolve out of the Planck scale as we zoom out - we just start summarizing the positions to save our damn sanity.

Einstein wasn’t just being conventional by suggesting that Space and Time be moved over to Space-Time.

Time = Distance, Distance = Time.
Physical objects have a surface, and traveling over or across surfaces is to travel distance, so distance is a very real property of physical objects in much the same way that their size and shape are.

Time…they don’t have.

Cheers,
Jayson