๐ Get exclusive NordVPN deal here โต https://NordVPN.com/floatheadphysics Itโs risk free with Nordโs 30 day money-back guarantee!โ
T shirts:
Link to ‘Don’t be dx3/dt3 T-shirt’ (Promo price)
Light: https://floatheadphysics.com/products/dont-be-a-jerk-light
Dark: https://floatheadphysics.com/products/dont-be-a-jerk-dark
Henrietta Swan Leavitt, an American astronomer hired as human computer made a startling discovery. Not only did it help humanity realise that the universe is teeming with billions of galaxies, but it led Edwin Hubble to eventually discover that the universe must be expanding, eventually leading to the big bang theory. The entire paradigm shift is centered around her discovery. But what exactly did she discover?
Chapters
00:00 The astronomer who made a startling discovery
01:07 Einstein’s cosmological constant
02:54 Friedmann’s counter argument against the constant
04:00 Vesto Slipher’s puzzling discovery of the spiral ‘nebulae’
07:40 The best measuring methods until the 1920s
09:04 A serious upgrade
10:50 Henrietta Levitt enters the story (Levitt’s Law)
16:15 The paradigm shifts after Levitt’s law
17:50 The Hubble Law
20:38 Einstein’s blunder, or was it?
This video was sponsored by Nord VPN
source
๐ Get exclusive NordVPN deal here โต https://NordVPN.com/floatheadphysics Itโs risk free with Nordโs 30 day money-back guarantee!โ
Leavitt was described as "hardworking and serious" but that "she had the happy, joyful, faculty of appreciating all that was worthy and lovable in others, and was possessed of a nature so full of sunshine that, to her, all of life became beautiful and full of meaning."
Hey scientists say that Universe is not just expanding but it's accelerating due to Dark Energy and Hubble Expansion rate or Hubble Constant is measured and it's one of the ways to tell the Age of Universe which is Roughly around 70 Km/sec/MPC but doesn't acceleration means that their could be a error in calculating the age of Universe then because generally we would think expansion to slow down after some time but it's not slowing rather it's accelerating so doesn't it create the age of Universe look much younger even though it might be older or is this descrepency have been taken care off I would love to know about it ?
A very big news is coming guys..๐idk when sir will reveal it here
Hii bro are you konkani ? Gsb?
Mahesh, you asked a few days ago why this video didn't do as well as the other ones. I think I know: *the title*. It should be "how do we know the universe expands".
People watching your videos are here to learn about the science and probably discovered you by searching big questions like "how time space curvature works" or "how relativity works".
We're not necessarily here for the history of science. We want to know how we can calculate galactic distances, not for a bio of Leavitt. Of course we love to know how standard candles were discovered and we're happy to learn who discovered it (she's really cool), but the title implies the video will more of a biography about her, which isn't what your channel and this video are about.
I wonder how there can be blueshift and redshift if the speed of the light is the same for every reference frame, and every light wave travels at C. If someone sees those waves compressed, his velocity with respect to speed of light has shifted. Red shift could be explained by gratitational lensing, with a prisma like behaviour, but no matter how fast the star is moving its lightwaves must reach you at the constant speed of light. No matter in which direction, towards you or away from you. That is the speed the waves of the visible frequencies are propagating which should remain constant.
Your videos are very intuitive ๐๐
For anyone wondering, the T shirt says don't be a jerk. Jerk is the rate of change of acceleration with respect to time.
***
Vote for Liouvilles Theorem.
totally unfair that Mahesh can talk with dead famous scientists and I can't
I'd never understood exactly how standard candles could have been used, but your video is the first to explain how it works. I think many science personalities think people can't understand those details, but you are proof that we can. It also helps that you explain it in easy, simple ways.
How do you know if the light from a galaxy is red-shifted if you don't know what the light should be like without the red-shift?
Or was it!? Love your channel for making the math become intuitive and therefor the concepts better understood. Your style is very comfortable and fun.
E=Mc^2 reality only makes dynamic systems. true measurements are impossible. We are the quantum in reality. Consciousness that is. Ihate the saying nothing happens in a vaccume when actually everything happens in a vaccume. It would seem realty is only as real as the ideas in our consciousness. Theyre as real as numbers. I cant physically interact with them but yet i kinda do it would seem theres dimensions involved. Is information physical. I think if we can conceive it, we can believe it. Could it really be as difficultly simple as faith? And we share a consciousness that reality is just an agreed arrangement that could be changed if we belived. But it would have to be done without knowing we were doing it figure a way to hack the consciousness network and retrain the model with an expansion pak kinda lol. I think the nazis tried some if thus kind of stuff on twins which not only unscientific but heinous to a degree not often reached.
I've been on a storm. Information is just dynamic motion capture. Information is relativity. Maths are the highest magnified base of reality. Maths are the microscope to Infinity. No measurement can be done in complete isolation that gives any usefulness it's use only comes from its relationship to all other information. There no static information. I have come to believe information it's self is responsible for the arrow of time. If physics is time symmetrical then it has to be measurable which means the universe has to store that somehow and does with action and reaction information read and transmit the order of operations gives a direction
very cool, took me a while to watch lol
I learned about Einstein's Loaf ๐ from Brian Greene's The Fabric of the Universe (or Cosmos). He discussed it in his book too. Quite simply, we think of lives as being in the now , but that's just an illusion of time. There is no now .๐ฎ
We know the past is real and don't think of it as something abstract; what happened in the past cannot change. I would argue that most reasonable person could be convinced of this.
๐
Here's the thing that really blows my mind; the future already exists! ๐คฏ
It might look random to us, but that's just not true.
Here's the real science that makes me believe this is true; time dilation predicted by Special Relatively has been verified by experiment.
The whole concept of Einstein's Loaf is just an extension of it to cosmic distances.
Here's what I just realized though; the Universe has already expanded itself out to infinite time and space.
It continues to blow my mind. ๐คฏ
We just haven't caught up with that point in the space-timeline where the Universe ends.
Amazed by explaining Distance coverage, although science establishes these measures, but seems like we are too small compared to what universe is in actual ๐
โญ๐๐ฏโค๏ธ๐
Ah – yes, how the steady state universe was disproven. Even as someone not versed in physics I remember this one from the hawking film starring Benedict Cumberbatch. That beautifull hiss.
Edit: Typo, beautiful was intended
"Let's calm down" damn I love your excitement. All kids should watch this video!
mahesh i had a question, "so i found out all humans give out infrared rays
and my tv uses infrared waves
so why don't the rays i emit accidentally cause my tv to do something?"
Happy Birthday sir…๐
Damn we were born 8 days apart from each other
A quick fix (probably) – in the 1920's we lived in Newton's world, that assumed an endless universe. So saying the milky way is in the center is meaningless. Earth as well understood not to be in the center of anything, including the milky way for a very long, before the 1920's
i think we are vastly underestimating the time dialation of cosmic voids. time moves differently in the absence of matter and therefore viewing light through these mediums can account for the red shift and thus the universe may be static afterall. prove me wrong
literally learned about 75% of the terms you introduced in this video i learned in my astrophysics 2 class that started this semester (about jan 12) so its crazy how im learning about all these new crazy concepts and you just so happen to make a video covering the same ideas and clearing up any confusion i ever had, reinforcing my pre-existing understandings, and teaching me so much more โค love the vids!!!
Space time is curved, but we can triangulate to calculate local stellar distances. Space is expanding but not on stellar, galactic or local cluster scales. But it is expanding at near light speed because reasons! Or maybe not?
Cosmology is dogma with no room for legitimate query or deviation from the orthodox big bang boloney.
why would you assume that all cepheid stars follow the same period/brightness as the ones being analyzed in that cluster? no matter how you put it, it is still an assumption that cannot be verified.
Hey Mahesh, I just want to begin with saying how you're one of the best physics youtubers on the platform and are the best to me at giving intuitive explanations.
I just wanted to suggest the topic of "De Broglie's Equation" because De Broglie's derivation is very very different from what's typically shown in textbooks which makes it seem like a simple manipulation of equations under rating his work, and another reason is, it's simply unintuitive, how does everything with mass have a wavelength? If so then a lot of questions pop up, like is there really a distinction between wave and matter? and many more that I can immediately think of. Thanks for reading this!
And now we come to realize that we are in the center of the universe after all. In fact, every point in the universe is in the center of the expanding universe. The universe is a forever expanding causality bubble that's originating from every point, and everything in it is just being dragged along for a ride.
4:49 ๐คฏ๐คฏ๐คฏ