Science!! Fucking magnets, how do they work?

Thread starter Flunklesnarkin_sl
Start date Dec 17, 2012

Troll_sl

shitlord

Oct 1, 2015

#3,821

Even if modified General Relativity was indeed correct (and it's been modified many times since its inception already, so it wouldn't surprise me), gravity waves would still be a logical outcome.

The problem is just how fucking weak gravity really is. It follows the inverse cube law, ffs. People have a hard time understanding how numbers behave (I know I do) and gravity seems so overwhelming from where we sit. But the amount of energy it takes for us to escape the planet is truly rather negligible on the scale of things.

Cad

scientia potentia est

<Bronze Donator>

Oct 1, 2015

#3,822

Troll_sl said:
Even if modified General Relativity was indeed correct (and it's been modified many times since its inception already, so it wouldn't surprise me), gravity waves would still be a logical outcome.

The problem is just how fucking weak gravity really is. It follows the inverse cube law, ffs. People have a hard time understanding how numbers behave (I know I do) and gravity seems so overwhelming from where we sit. But the amount of energy it takes for us to escape the planet is truly rather negligible on the scale of things.

Okay, but we can calculate the force the Sun is exerting on the earth at any given time, right? And I can only assume that it is a very large number. Can we not detect anything about that gravity, except the force itself?

Note: I'm not Furry-izing it, I genuinely don't know and I want someone to explain it to me.

Ambiturner

Ssraeszha Raider

Oct 1, 2015

#3,823

The amount of gravitational radiation between the sun and earth would be much harder to detect that from much more massive objects lounge black holes, binary pulsars, etc.

Cad

scientia potentia est

<Bronze Donator>

Oct 1, 2015

#3,824

Ambiturner_sl said:
The amount of gravitational radiation between the sun and earth would be much harder to detect that from much more massive objects lounge black holes, binary pulsars, etc.

But we're much closer to the sun, so inverse square law right? Supermassive black holes would have insane gravitation but also be very far away.

Lendarios

Trump's Staff

<Gold Donor>

Oct 1, 2015

#3,825

The /R^2 makes the gravitational force super small the farther you are, imagine, just 1 light year away means dividing by 8.95015976147 ? 10^31. and the closes celestial body to us is "only" 4.24 ly away, imagine dividing by that..

Troll_sl

shitlord

Oct 1, 2015

#3,826

Cad_sl said:
Okay, but we can calculate the force the Sun is exerting on the earth at any given time, right? And I can only assume that it is a very large number. Can we not detect anything about that gravity, except the force itself?

Note: I'm not Furry-izing it, I genuinely don't know and I want someone to explain it to me.

I don't know if we've ever actually put up any instruments sensitive enough to measure the gravitational pull of the sun. I wouldn't be surprised, but it'd also still be incredibly weak this far out. Our calculations are pretty precise, though, thanks to Newton (and lots of incremental improvements since then). The moon, however, has much more influence on us than the sun, despite the mass difference. Distance really does make that much of a difference.

From what I've heard, one of the difficulties we'll have with instruments like ALIGO or eLISA will be differentiating gravitational waves from the sun's pull.

Troll_sl

shitlord

Oct 1, 2015

#3,827

Investigating further. From wikipedia's LIGO entry:

Based on current models of astronomical events, and the predictions of the general theory of relativity, gravitational waves that originate tens of millions of light years from Earth are expected to distort the 4 kilometer mirror spacing by about 10^-18 m, less than one-thousandth the charge diameter of a proton.

The charge radius is 0.8775(51)*10^-15 meters, though it may be smaller still. And we're talking about detecting waves from objects millions of lightyears away.

Edit: Just to help it sink in. That's about .0000000000000008775 meters.

Picasso3

Silver Baronet of the Realm

Oct 1, 2015

#3,828

Troll_sl said:
I don't know if we've ever actually put up any instruments sensitive enough to measure the gravitational pull of the sun. I wouldn't be surprised, but it'd also still be incredibly weak this far out. Our calculations are pretty precise, though, thanks to Newton (and lots of incremental improvements since then). The moon, however, has much more influence on us than the sun, despite the mass difference. Distance really does make that much of a difference.

From what I've heard, one of the difficulties we'll have with instruments like ALIGO or eLISA will be differentiating gravitational waves from the sun's pull.

The sun exerts more gravitational force on the moon that the earth does per newton's law of gravitation which you can plug the shit in and in about 4 minutes have your answer.
I think someone in like 1500 came up with a way to measure gravity with some strings and shit.

This gravity waves debate is far past that, I think. Probably like bringing up how hard the wind blows when you're discussing particle physics.

Furry

WoW Office

<Gold Donor>

Oct 1, 2015

#3,829

Tuco_sl said:
Or is Furry's position simply that we haven't experimentally proven the existence of gravity waves, therefore the people who assume they exist are wrong?

That's the majority of my position. I believe that gravity waves are a neat idea until they are proven to exist. I won't accept indirect evidence, especially when its indirect evidence from HYPOTHESIZED SYSTEMS, because indirect evidence like that is not trustworthy scientifically for numerous reasons. Thankfully, we have the ability to get direct evidence on this subject, and have built machines capable of getting said indirect evidence. So that is and should be scientifically the number one way of determining the truth of this subject.

If gravity waves exist, These machines are far more likely to have detected an event so far than not. That is a simple scientific fact.

Troll_sl said:
That's about .0000000000000008775 meters.

Last I checked, LIGO can detect signals in optimal conditions at a strength of 1*10^-23, which is incredibly more sensitive than that. Reliably, in the poorest conditions it can still detect in the 1.0*10^-20 range. Why do you keep going to this claim that it is really hard to detect, when the machine is built, tested and verified to detect these signals accurately.

Ambiturner

Ssraeszha Raider

Oct 1, 2015

#3,830

Cad_sl said:
But we're much closer to the sun, so inverse square law right? Supermassive black holes would have insane gravitation but also be very far away.

Not exactly. The "ripples" are mostly based on non-spherically symmetric bodies acceleration, so it's negligible from the Sun.

Also, while the moon is much closer and we are definitely affected by its gravity, that's not the same thing as emitting detectable gravity waves.

Cad

scientia potentia est

<Bronze Donator>

Oct 1, 2015

#3,831

Ambiturner_sl said:
Not exactly. The "ripples" are mostly based on non-spherically symmetric bodies acceleration, so it's negligible from the Sun.

Also, while the moon is much closer and we are definitely affected by its gravity, that's not the same thing as emitting detectable gravity waves.

So, if I'm reading you right, gravity waves aren't like light waves where the "effect" of gravity is carried by the waves. If thats true, what carries the "effect" of gravity?

Furry

WoW Office

<Gold Donor>

Oct 1, 2015

#3,832

The funny thing is, There literally is no examples of anything except gravity being 100% instantaneous action in observed science. It is always calculated in applied math as instantaneous action. The existence of gravity waves is a huge mathematical mess where gravity is allowed to act instantly, but the propagation of new information of its strength is limited to the speed of light. It requires some strange logical mind bending, like the acceptance that gravity itself is a field that permeates all of space, rather than a force that is emitted from sources. It leads to lots of strange logical problems in accepting how it works, such as the field itself is required to known in advance where the body it is following is going, which in essence is an attempt to hide the FTL force of gravity from laymen mathematicians, but it does work mathematically.

To me, the gravity part of General relativity is silly, but its not nearly as fundamentally broken at every level as QE is.

hodj

Vox Populi Jihadi

<Silver Donator>

Oct 1, 2015

#3,833

Cad_sl said:
If thats true, what carries the "effect" of gravity?

Space time.

Imagine a blanket that's been pulled out by all four corners really tightly that you bounce a ball on. The ripples in the fabric as the ball interacts with it would be the gravity waves.

Its not a perfect example but I think its a fairly decent one for our purposes.

Cad

scientia potentia est

<Bronze Donator>

Oct 1, 2015

#3,834

hodj_sl said:
Space time.

Imagine a blanket that's been pulled out by all four corners really tightly that you bounce a ball on. The ripples in the fabric as the ball interacts with it would be the gravity waves.

Its not a perfect example but I think its a fairly decent one for our purposes.

So, if I imagine space time as a blanket, and the mass of a ball distorts the shape of the blanket (this would be gravity's effect on spacetime), And lets say I apply a force to that ball so that the "distortion" isn't stationary. Are we saying that the changes in distortion propogate across space time at the speed of light? Because for example, if I'm pulling on a rope and suddenly let go, there's no real time delay for that to be felt at the other end is there? Just the elasticity of the rope I guess. Am I carrying this metaphor too far?

hodj

Vox Populi Jihadi

<Silver Donator>

Oct 1, 2015

#3,835

Cad_sl said:
So, if I imagine space time as a blanket, and the mass of a ball distorts the shape of the blanket (this would be gravity's effect on spacetime), And lets say I apply a force to that ball so that the "distortion" isn't stationary. Are we saying that the changes in distortion propogate across space time at the speed of light? Because for example, if I'm pulling on a rope and suddenly let go, there's no real time delay for that to be felt at the other end is there? Just the elasticity of the rope I guess. Am I carrying this metaphor too far?

Speed of light is ~300,000,000 m/s (a little less but close enough we can just round it off there) so if they're propagating at or near it, it still takes X amount of time for that force to travel to whatever place, even if that speed is very very fast.

Speed of gravity - Wikipedia, the free encyclopedia

In classical theories of gravitation, the speed of gravity is the speed at which changes in a gravitational field propagate. This is the speed at which a change in the distribution of energy and momentum of matter results in subsequent alteration, at a distance, of the gravitational field which it produces. In a more physically correct sense, the "speed of gravity" refers to the speed of a gravitational wave, which in turn is the same speed as the speed of light (c).

But yes, it appears the speed of these waves should be at or near the speed of light.

Added: But much like the ripples in a pond or a blanket with a ball bouncing on it, as the waves spread out, they get thinner/smaller, and so become even harder to detect as they progress.

Ambiturner

Ssraeszha Raider

Oct 1, 2015

#3,836

Furry_sl said:
The funny thing is, There literally is no examples of anything except gravity being 100% instantaneous action in observed science. It is always calculated in applied math as instantaneous action.

Bullshit. What actual data do you have that shows it moving instantaneously?

hodj

Vox Populi Jihadi

<Silver Donator>

Oct 1, 2015

#3,837

Its just more of that mistaking the clay figurine for the person its modeled on mentality.

Ambiturner

Ssraeszha Raider

Oct 1, 2015

#3,838

Him pretending he's being a responsible scientist by not believing in gravitational waves without direct observation is absolutely ridiculous. NOT believing in them would be the dramatic leap of faith he's claiming the rest of credible scientists are engaging in.

He keeps repeating his line that the fact that we haven't detected gravitational waves is because they probably don't exist. That we have had perfect experiments that were GUARANTEED to find them if they were actually out there. That is not true and none of the scientists involved in the experiments believed that, either. He just has it ingrained that he has to go against accepted scientific theory to make himself feel superior. He also lacks understanding of very basic concepts and thinks you can cherry pick parts of a theory regardless of how they may depend on each other.

He still hasn't responded on how he thinks GR can be accurate except for gravitational waves and still exist intact

Furry

WoW Office

<Gold Donor>

Oct 1, 2015

#3,839

Ambiturner_sl said:
He still hasn't responded on how he thinks GR can be accurate except for gravitational waves and still exist intact

Why should I care about or try to explain this? Some parts are observationally true, yet this one appears to likely be observationally false. It would mean the theory is observationally broken, but I'm not here to do anything other than say that part of the theory appears to be observationally broken. You can do whatever you want with that, I don't have any agenda to push other than being truthful with science and math.

Picasso3

Silver Baronet of the Realm

Oct 1, 2015

#3,840

Pretty much every time i open this thread it's furry disagreeing with some publication or seemingly accepted theory...you have wonder how many peer reviewed articles and Nobel prize winners are dead wrong... per furry it's all of them, always.

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