Recent content by Pentcho Valev

Richard Feynman: "I want to emphasize that light comes in this form - particles. It is very important to know that light behaves like particles, especially for those of you who have gone to school, where you probably learned something about light behaving like waves. I'm telling you the way it...

View: https://x.com/pentcho_valev/status/1923265482280370418 ME GIF: Observer changes his speed and sees distances between light pulses vary so that speed of light relative to him remains constant. Special relativity says so, doesn't it, @grok? Future, Einstein-free physics: Distances'...

View: https://x.com/pentcho_valev/status/1922907883563258068 ME Grok, Elon Musk's AI device, claims that 1. in vacuum, the wavelength of light is fixed, invariable, constant (depends only on the nature of the emitting body). 2. due to relativistic effects, the observer SEES the fixed...

View: https://x.com/grok/status/1921656612835700887 GROK When you were 2, your sister was 4 (twice your age). Now at 40, without relativity, she’d be 42. If she’s moving at near-light speed, time dilation applies: time slows for her. At 99.9% light speed, she’d age about 1.7 years in 38 years...

View: https://x.com/grok/status/1921520396094058581 GROK Gravity is not required for time dilation. Special relativity shows that relative velocity alone can cause time dilation, as seen in cosmic muons traveling near light speed, which decay slower, allowing them to reach Earth. In deep...

View: https://x.com/grok/status/1921502404488655004 GROK The universe is widely accepted to be expanding, supported by redshift, cosmic microwave background, and supernovae data. The idea of matter shrinking is a speculative alternative lacking empirical support. Black holes are predicted to...

Brian Greene teaches ASYMMETRIC time dilation: The moving clock is slow, the stationary one is fast: View: https://youtu.be/Q1y3YnPgaY4?t=1157 Asymmetric time dilation is non sequitur - doesn't follow from Einstein's 1905 postulates. The postulates, true or false, entail SYMMETRIC time...

View: https://x.com/pentcho_valev/status/1920469585238597722 ME Ask Perplexity: "Special relativity predicts that a traveler moving at high speed will experience time more slowly than people who remain stationary" I'm afraid not. It only predicts that the traveler sees stationary clocks...

"If another person's clock runs slower than yours, then yours is running faster than theirs." That's what I have said. "But yours does not speed up and run faster than it was, nor does the other run slower than it was running." This is an objection to what I have not said.

View: https://x.com/grok/status/1918903460935991739 GROK Time dilation means time passes slower for someone moving fast, like on a spaceship, compared to someone still, like on Earth. It’s from Einstein’s special relativity, where light’s speed is always the same. For example, a clock on a fast...

"In astrophysics, gravitational redshift or Einstein shift is the process by which electromagnetic radiation originating from a source that is in gravitational field is reduced in frequency, or redshifted, when observed in a region of a weaker gravitational field. This is a direct result of...

Einstein's relativity has a preposterous prediction: The speed of light decreases as light falls towards the source of gravity, and increases as light ascends. Theoretical physicists find this prediction too dangerous and never discuss it. Still they know that absolute secrecy is impossible, and...

"When the observer is moving, as in Animation 2, the sound waves emitted from the source are undisturbed. The wavelength does not change as observed from the moving observer." https://www.compadre.org/osp/EJSS/3851/model5/85.htm Unchanged wavelength implies that the speed of the waves relative...

Grok (Elon Musk's AI): "Einstein's 1918 argument on the Twin Paradox used general relativity, suggesting the traveling twin, during acceleration, experiences a gravitational field where the stay-at-home twin's clock runs faster, making them older upon reunion. However, this idea of a...

Two texts suggesting that the speed of light is VARIABLE (goodbye relativity, goodbye modern physics): "Vo is the velocity of an observer moving towards the source. This velocity is independent of the motion of the source. Hence, the velocity of waves relative to the observer is c + Vo...The...