Gravitational waves for dummies

[sygn]

I wasted hours of my life reading news articles, but I still couldn't grasp this concept.
And through no fault of mine; most of them did a poor job in translating highly complex concepts, in a manner simple enough for laypeople to understand.

However, I just came across this fantastic 5 mins. minilecture accompanied by animations & computer simulations.
Which, according to youtubers' comments, is perhaps the best, easiest to understand vid. on spacetime.

 

[sygn]

To start off: What is Space-Time ?

https://www.youtube.com/watch?v=sryrZwYguRQ
by Stéphane Durand (umontreal).
Some excerpts:

Introduction
"Relativity theory says that contrary to what our senses tell us, we live not in a three-dimensional space, but in a spacetime that has four dimensions, time being the fourth dimension. However, our senses cannot perceive more than there dimensions, therefore it's difficult to visualize a forth dimension."

1.00 - 2.50 : (Must see animations accompanying the explanations)

"What is perceptible by the senses is what appears in the slit at a given moment.
-- When we remove the slit and we see the full figure moving, we place ourselves in the position of a sort of God who lives outside of time and outside of space. We see all the moments at the same time: The start, a bit later, and later.
-- We (people) cannot normally perceive this moving figure in full. We see only a slice of it, that slices with the passage of time. We must, therefore, distinguish the space which is perceptible by the senses, and the space-time, which is beyond the senses."

3.54 - 4.04
Computer-simulated graphic of the spacetime of a dancer in motion.













ETA
I couldn't C&P the animations / diagrams from mins. 1.00- 2.50, but this one is a pretty good substitute:

https://einstein.stanford.edu/Library/images/lightcone.gif

 

[rae121452]

i prefer peristaltic waves.

 

[sygn]

Fantastic start, but I still fail to grasp these:

"Gravitational waves are ripples' in space-time.
Massive accelerating objects would disrupt space-time in such a way that (...)
These cosmic ripples would travel at the speed of light, carrying with them information about their origins, as well as clues to the nature of gravity itself."
https://www.ligo.caltech.edu/page/what-are-gw



I might search for similar videos when I have time, but maybe someone has a quicker, good explanation & source?

 

[Ann_Tagonist]

I wasted hours of my life reading....

That right there is why I quit reading.

 

[sygn]

That right there is why I quit reading.

good one.

 

[sygn]

THE LIGO STUDY THAT SHOWED HOW GRAVITATIONAL WAVES AFFECT OBJECTS ON EARTH"


LIGO= the billion-dollar Laser Interferometer Gravitational-Wave Observatory

"Here's the quick lowdown on gravitational waves:
When two massive objects such as neutron stars or black holes collide, they send shockwaves through the Universe, rippling the very fabric of space-time itself.
This effect was predicted by Einstein in his theory of general relativity in 1916, but it wasn't until 2015 that we finally had equipment sensitive enough to detect the ripples.

That equipment is an interferometer that shoots two or more laser beams down arms that are several kilometres in length. The wavelengths of these laser beams interfere to cancel each other out, so, normally, no light hits the instrument's photodetectors.
--- But when a gravitational wave hits, the warping of space-time causes these laser beams to oscillate, shrinking and stretching. This means that their interference pattern is disrupted, and they no longer cancel each other out - so the laser hits the photodetector. The pattern of the light that hits can tell scientists about the event that created the wave.
--- As the ripples in space-time propagate, they can change the velocity, acceleration, trajectories and relative positions of objects and particles in their way.

Another observable effect is time dilation, whereby a strong gravitational field slows time.
Because gravitational waves warp both space and time, two extremely precise and synchronised clocks in different locations, such as atomic clocks, could be affected by gravitational waves, showing different times after the waves have passed."

https://www.sciencealert.com/gravit...ving-some-weird-lasting-effects-in-their-wake
, may 2019

 

[sygn]

AND NOW FROM THE MOUTH 0F THE EXPERTS, A CONCLUSION:

Scientists are on the verge of being able to detect the "memory" left behind by gravitational waves.
By Paul Sutter, astrophysicist, December 06, 2019

https://www******.com/gravitational-waves-memory-space-time.html

"The gravitational waves ripple throughout the universe, washing over the Earth.
When they do, they ever-so-slightly (as in, less than the width of an atom) move things around.

Even you. Right now, you are being gently squeezed and stretched by gravitational waves from violent events billions of light-years away.
---As gravitational waves ripple through space-time, they become a source of new (weaker) gravitational waves, which (...). The effect builds up into what scientists call a space-time "memory"

In other words, when gravitational waves wash over you, you don't just stretch and squeeze temporarily. When all is said and done, you are left permanently stretched."

 

[HisArpy]

AND NOW FROM THE MOUTH 0F THE EXPERTS, A CONCLUSION:

Scientists are on the verge of being able to detect the "memory" left behind by gravitational waves.
By Paul Sutter, astrophysicist, December 06, 2019

https://www******.com/gravitational-waves-memory-space-time.html

"The gravitational waves ripple throughout the universe, washing over the Earth.
When they do, they ever-so-slightly (as in, less than the width of an atom) move things around.

Even you. Right now, you are being gently squeezed and stretched by gravitational waves[/B] from violent events billions of light-years away.
---As gravitational waves ripple through space-time, they become a source of new (weaker) gravitational waves, which (...). The effect builds up into what scientists call a space-time "memory"

In other words, when gravitational waves wash over you, you don't just stretch and squeeze temporarily. When all is said and done, you are left permanently stretched."

And here my mom always told me that the reason I'm so tall is because I ate my vegetables and grew up.

Just think, I coulda saved myself from eating all them green things if my mom only knew this scientific fact.

 

[von_Bismarck]

Fantastic start, but I still fail to grasp these:

"Gravitational waves are ripples' in space-time.
Massive accelerating objects would disrupt space-time in such a way that (...)
These cosmic ripples would travel at the speed of light, carrying with them information about their origins, as well as clues to the nature of gravity itself."
https://www.ligo.caltech.edu/page/what-are-gw



I might search for similar videos when I have time, but maybe someone has a quicker, good explanation & source?

I like these guys for solid, popular-level presentations. https://youtu.be/1Tstyqz2g7o

 

[Dribble]

Lol...if you drop an apple...it looks as if "gravity" pulls it to the Earth's surface. This is an optical illusion. The Earth, because its mass is greater than the apple, actually has disrupted the spacetime fabric greater, which results in gravity...and therefore, it is the Earth ( with you as a reference) that actually moves toward the apple. People try to visualize this, but our brains only can see in 3 dimensions, so they fail. Spacetime, is a 4 dimensional reality. Pretty cool stuff

We can freely move around in space...forward, backward, up, down, left, right, even ending up where we started if we choose. But time, in unidirectional. It flows. One way. Now, there is nothing mathematically that says this must be. There are no rules of physics preventing time travel. So why does it go only in one direction? We dont know. But there is one other property that is unidirectional, and this is entropy. If you place an object in a vacuum, it moves towards a more disordered state. Is this fact, what limits time travel?

This thread will go over the deplorables head's...they cant understand, once the House impeached their leader...he remains impeached for all of history...how can they grasp spacetime fundamentals?

 

[Dribble]

https://www******.com/einstein-general-relativity-frame-dragging.html

I like the analogy of submerging a rotating object in honey...and the honey starts to spin. Why we were able to see this is because of the white dwarf and neutron star rotating around each other. If it was just one, we have no frame of reference, but with two we can detect the swirling of spacetime.

 

[jomar]

Chuck Norris dropped an apple once, and gravity was born.

 

[jomar]

Chuck Norris can detect gravitational waves with his penis.

 

[sygn]

I like these guys for solid, popular-level presentations. https://youtu.be/1Tstyqz2g7o

Awesome easy to understand vid., thanks.

So -am I correct?- physicists and scientists (but also philosophers and psychologists) are gradually moving away from the cartesian - Newtonian black and white split: mind versus matter, 'science' (including social sciences) and religion/spirituality, which has dominated modern Western thought.

Did Newton and Descartes (distorting the tradition of ancient Greeks) corrupt Western thought and make it less holistic?

Will the confirmation of yet another Einstein (the timespace) theory bridge the gap between Western science and religion? Einstein was agnostic, and admired budhism.

Ole to Jews.