Is Gravity An Illusion? | Space Time | PBS Digital Studios

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1. i unsubscribed because of this commentary from the planet shiteria.
2. According to that logic the earth will shake like vibrator 24×7 whenever thing stays on air earth started moving towards object.
3. No "f". it's "v". Elevating Earth with steady velocity. #FlatEarth :)
4. So that means that the spin and acceleration of the earth plus the curvature of space time is what keeps us in our orbit right?
5. Symmetra : Death is an illusion.
6. Dang I can't finish my coffee peacefully whenever I watch a PBS Space Time video.. It's just too heavy.
7. Dang I can't finish my coffee peacefully whenever I watch a PBS Space Time video.. It's just too heavy.
8. Gravity does not exist man! gravity theory is advanced fiction. When you go forward the trees go (move backward)? Never. You you can go forward. Trees never move. Therefore, relativity theory is delusion. Understand?
9. brilliant video.....but sir can you plesae speak slowly.......i had to watch this video 4 times to understand it.......its my humble respect
10. WHY DOES THIS GUY SHOUT EVERYTHING HE SAYS AT SPEED LIKE THE VIEWER IS REALLY FAR AWAY AND ONLY BY SHOUTING WILL HE EVER GET HEARD AND ONLY BY TALKING QUITE FAST WILL HE BE ABLE TO GET OUT EVERYTHING HE WANTS TO SAY :(
11. My thought is that everything is expanding. The earth is expanding and even the apple is expanding. The earth just has more to expand. I think if you look at the universe and gravity that way, everything is also consistent.
12. If the ground is accelerating up to the apple how is that happening to apples simultaneously on opposite sides of the earth?
13. Good clarity. As a beginner who is (finally) taking the step from special to general relativity on YouTube, this was enlightening.
14. Planet Earth emit a radio wave each time it is accelerated. Normally, we would go in straight line, but this massive sun, 1 million time our size, keep forcing us to deviate from that line. This deviation is creating a radio wave with the main frequency of 1 year and a few (infinite number of) harmonics with frequencies of 6 months, 3 months, etc
    
    If the Earth was exactly in a circle orbit, this wave of 1 year wavelength would be a purely sinusoidal. Because of the ellipse, some higher frequency components are also radiated. The rotation of Earth, because the iron core is not homogeneous add some radiation with wavelength of 1 day. The tilt of Earth rotation also impact the ratio of harmonics.
    
    Brief, if some alien would use very sensitive magnetometer / electrometer (a giant antenna), they would detect an electric current that would slowly raise for 6 months and slowly decrease for 6 months. That wave would also have some much smaller variations every 6 months, 3 months, 6 weeks, etc. There would be also other frequency components not harmonically related to the 1 year main frequency.
    
    Simultaneously with the 1 year radio wave, the Earth also transmit a 1 year gravitational wave. There is no harmonic, it is a pure sinusoidal wave. The elliptic orbit do not impact this gravitational wave because that orbit is exclusively determined by gravity ; an equilibrium is always garanteed in the same way as an helium balloon in stationary vertical position or a submarine with ballast filled just right to maintain position is, in equilibrium with the entire mass of the atmosphere or the ocean water.
15. still for me.. newton is the man! He is the greatest scientist ever!
16. rlly flat earth.. not on this channel please...
17. Backwards jolt is not an illusion - the acceleration is transferred to your body from the car via your legs and/or butt (depending on your pose) which are in contact with the car. Your head and body being not 100 percent rigid take some time to get this acceleration. That is all. Nothing magical about it. And considering your point that it is Earth that pushes up not apple or anything falling down - that is also untrue - just make two apples fall at the same time on the opposite sides of the Earth and... they will both fall at the same time. That means that Earth is stationary, because otherwise one of the apples would fall later than the other or wouldn't fall at all because Earth cannot "jump" in two opposite directions at the same time.
18. Very nice!
19. ok the video ytou supplied include a very bad ttest of a drop ball! dont believe me? try to make it curve in any way you know how to using similar tool!  got it ? now go see veritasium channel and view his soccer ball drop from a dam and afterward the spin he induced ,just inducing a spin created chaos that made the move unpredictable . and you? you think this test is accurate in the black and white video? trust me its irelevent? since in the universe thing dont happen that way . why there is an issue? because any time magnet is included in a test? the thing being tested is magnetised! so once Something is magnetised it will follow on rail anything around made of metal ! in this case the bar behind the ball! error 1
    error 2? ever tried to make Something else go straight like the magnet does? you should! like a glass ball ! and the thing behind made of glass
20. Hm... so if I have two people each holding an identically massed apple at exactly the same distance from the center of the planet on either side of the Earth and have them let go at the exact same time.. they won't fall because the Earth can't stretch in both directions at the same time enough to reach the apple?
    
    That seems unlikely...