Full podcast episode: kzfaq.info/get/bejne/qsqmatVjr7nTm30.html Lex Fridman podcast channel: kzfaq.info Guest bio: Sean Carroll is a theoretical physicist, author, and host of Mindscape podcast.

He has a great voice. Carrol is one of the most respected science communicators and scientific theorists in his field.

Sean at his best. Some new and interesting facts about Einstein's gravitas. A stepped-up version of Lex, too. Good clip.

Einstein published 3 papers all in 1905 - Light as particles and not just waves, special relativity, and proof that atoms exist. That's incredible, that's genius.

Fun fact kids. Dynamic Gravity explains all perfectly and its math actually perfectly calculates gravity, dark energy, and dark matter with the same equation. And there are no paradoxs like GR. Its just a better theory of gravity.

Can someone explain to me why: over the last 50 years of studying black holes, we learned that the clock slows down as you approach the event horizon (go deeper into the gravity well). But nobody has proposed that there could be higher gravity potential energy "planes" or "dimensions" where the clock runs faster. Like a skyscraper where the event horizon is in the basement, we are in the first floor. The clock runs faster on the second floor, so that spaceships can move faster on the second gravitational floor or dimension. Maybe you have to get to the 50th gravity floor, where the clock runs 50x as fast, before you can think about using the 50th floor for interstellar travel.

Thank you for crediting Minkowski

I like Lex, he's a very good interviewer

So special relativity is based on the Michelson-Morley experiment (1887), which found that the speed of light is the same for all observers. This seems ridiculous based on classical intuition, but once you've accepted it as confirmed fact, SR follows from it directly. Einstein's genius was being completely open-minded about following confirmed truths to their logical conclusions. The motivation for general relativity is even older: It had been known since Newton's time that inertial mass (resistance to acceleration) and gravitational mass (mutual attraction of massive objects) are exactly the same. Again, from a conceptual standpoint, all Einstein had to do (in addition to the math of GR, which is much harder than SR) was clear his mind of traditional assumptions and find the theory implied by that simple, universal fact.

no, it wasn't Einstein, not even Minkowski, who realised that space and time form a unity. it was Lorentz. Lorentz was the one who understood first how abstract algebra is related to spacetime and to relativity. he developed the Lorentz-symmetry group and so the Lorentz-transformation. and he was the one who proposed to treat space and time as one. actually Einstein just used Lorentz' insights and defined the two postulates of relativity. most of the credit should go to Lorentz. just like the electromagnetism was mainly described by Faraday, he was the one who realised that electric field and magnetic field are two aspects of the same thing, he invented the concept of field lines, and he realised all the four principal laws of electromagnetism. but his mathematical background was poor, so Maxwell formalised these laws using vector calculus (which was a new thing back at that time). and no, this "explanation" does not lead to real understanding, at most to superficial knowledge and so to an illusion of understanding. in order to deeply understand relativity, you must understand its underlying mathematics and its relationship with other physical laws. this is something that you cannot spare. not even when someone explains well the given theory and its certain aspects. e.g.: - the relationship of gravity with electromagnetism, their symmetry properties, bosons and graviton, linearity (vector field description, i.e. antisymmetric tensorial description) [spin-1 boson (photon) and symmetric sources (charges)] vs nonlinearity (tensor field description, i.e. symmetric tensorial description) [spin-2 boson (graviton) and symmetry breaking sources (masses)], Maxwell-equations and gravitoelectromagnetism, field theory (quantum) based description vs geometrical (relativistic) based description etc. - curvature, as frequency and spectrum from Fourier-analysis (x-k duality) - force, as a human-made construct and concept: in fact, gravitation is not a force, but an interaction, and in the sense of relativity, gravitation manifests itself through the curvature of space-time, i.e. the rotation of the light cone (i.e. the gradual exchange of the roles of space and time). ergo: relativity eliminates the concept of force and its necessity and legitimacy by including and extending Euclidean space (to non-flat, i.e. curved non-Euclidean spaces), the concept of straightness (to geodetic lines) and the concept of inertia (to motion alongside geodetic lines). not to mention the even deeper aspects of reality which share characteristics with quantum physics (e.g. the introduction of the observer, i.e. the subject, and so the subject-centred nature of the object, i.e. of reality).

I am so much dumber now after reading these comments 🤦‍♂️

Comment section is bunch of people trying to sound smart saying stupid shit

GRAVITY EXPLAINED, universe is made of minute cells once contained in a universal shell that was broken or deformed by an external force. this produced expansion creating a true void that must not exist, leaving the cells to expand or split,I believe the destruction or splitting of cells is where all matter originates, therefore all the contents of this universe will become matter and the universal matter will disperse or be contained by an outer external force or medium. The cells must penetrate already created matter to a degree, becoming harder the denser it is, until it is so dense it is impossible. thus the push back is multiplied infinitely causing corresponding gravity push... As far as so-called gravity it is plain to see that there is no attraction, only an external push forcing matter together . Imagine an oil filled rubber ball each molecule of oil must have the same force upon it. Then introduce a foreign particle of the same size and density then each molecule will have slightly higher pressure upon it nothing will coalesce then add a larger or denser body with larger or harder surface to be pushed upon by the other molecules all the molecules will feel a small amount more push but the nearer the large body cells will get pushed harder. [this energy really comes from the constant push from the ball membrane or what exists outside it] then introduce a smaller dense body in the vicinity of the harder pushed cells. if the number of hard pushed cells behind this body is higher than the ones between it and the large body then gravity is achieved,,,unless the pull from the expanding universe shell is greater.. Without resistance to these cells energy would not be forced to navigate a wave pattern, the cells would not become excited and light as we know it would not exist . Energy waves passing through harder pushed cell formations will deviate around the reason they are pushed. Hard pushed cells may be deformed from a sphere into an ovoid making it harder to rotate, also making energy travel differently The universe itself may be such an ovoid thus the reason for expansion. Magnets must electronically rearrange the cells shape and alignment making the rearranging object harder or easier to navigate between depending the manufactured configuration. As far as Quantum physics goes we do not have any real data so mathematical physics is applied and comes up with sometimes fanciful answers to fit a paradox. Understanding a data lacking subject has always failed people already in this field would do best just striving for accurate observation as some early astronomers did. An understanding will develop with detection instruments and supercomputing enhancements , seeing it first hand. some bright spark will discover the bleeding obvious and mathematise it. We must determine the size and density of each cell by measuring each light wave in relation to one another ,and the number of cells between each crest and finding the correlation that would fit all known energy waves if this can be achieved, the next step must be to create corresponding energy waves before a moving object creating an air in sand effect thus help said object closer to the preceding wave speed Initial measurements should be simple two dimensional with known wave patterns overlaid on the same plane and begin with spherical solid cells filling the voids between the crests of all waves. First, hoping all the energy waves respect the integrity of each cell, if not some types of energy waves may penetrate part of the cell, as do they penetrate some matter. black holes are remnant void bubbles still trying to eliminate the space where cells are absent,destroying surrounding cells and creating matter and drawing existing matter to fill the void .billions may have succeeded leaving small super dense spheres but most can't keep up with the constant universe expansion and will take all their surrounding galaxy and more. No matter how beautiful and pleasant maths is , since the mid 60's, it has blinded physicists before then a physical notion was envisaged then came out the ruler to see if it would stack up. These are some answers to how things unfolded but surely the harder question is why. Why has life evolved to a stage that we can pose these questions? Surely non existence would be the easier option ,without struggle without knowing about your inevitable destruction personally and universally this question is the real puzzle. This is why the emergence of conscience coincided with a genetic predisposition towards a god culture everywhere on earth ,a genetic valium so to speak. which must be ameliorated not railed against by atheist dissenters , its just DNA evolved a part of our bodies to believe so as to survive longer. The answer can only be chemistry ,all life is simply a chemical reaction , the same as the stars react with each other ,no matter how complicated its components become it must rely on the basic building blocks to exist ,my thoughts while writing this are governed by a chemical reaction and the lightning created by the reaction. Therefore if matter has no will and the meeting of different types of matter will react differently then the meaning of life has the same weight as mixing paint ,And in theory the universe could become sentient itself, life and death is eventually inevitable wherever matter coalesces .

Lightspeed is fixed at 300,000km/sec because light is electromagnetic radiation and it's speed is being throttled by the permeability and permittivity of space itself. Maybe "aether" is just a metaphor for the resistance of space in limiting the speed of light.

It is odd to me that it is considered an accomplishment that they got rid of the aether, but then immediately replaced it with space-time and quantum fields. It seems like the aether never went away. They just got better at describing it.

Theorem 7: The vacuum expectation value of the energy-momentum tensor in general relativity is proportional to the metric tensor. Proof: In general relativity, the energy-momentum tensor T_μν is a symmetric second-rank tensor that describes the density and flux of energy and momentum in spacetime. The vacuum expectation value of T_μν, denoted by ⟨0|T_μν|0⟩, is the expectation value of T_μν in the vacuum state |0⟩. According to the Einstein field equations, the energy-momentum tensor is related to the curvature of spacetime via: R_μν - (1/2)Rg_μν + Λg_μν = (8πG/c^4) T_μν where R_μν is the Ricci tensor, R is the scalar curvature, g_μν is the metric tensor, Λ is the cosmological constant, G is Newton's gravitational constant, and c is the speed of light. In the vacuum state, the energy-momentum tensor vanishes classically, i.e., T_μν = 0. However, in quantum field theory, the vacuum state has zero-point fluctuations that give rise to a non-zero vacuum expectation value of T_μν. By the principle of general covariance, the vacuum expectation value of T_μν must be proportional to the only available second-rank tensor in the vacuum, which is the metric tensor g_μν: ⟨0|T_μν|0⟩ = κg_μν where κ is a constant. Substituting this into the Einstein field equations, we obtain: R_μν - (1/2)Rg_μν + Λg_μν = (8πG/c^4) κg_μν This implies that the vacuum energy-momentum tensor acts like a cosmological constant term in the Einstein equations, with an effective cosmological constant given by: Λ_eff = Λ + (8πG/c^4) κ The fact that the vacuum expectation value of the energy-momentum tensor is proportional to the metric tensor suggests that the concept of zero or nothingness may be deeply connected to the geometry and topology of spacetime, and may play a crucial role in the large-scale structure and evolution of the universe.

First, and foremost, all of the actual hard work that underlies Einstein's work was done by other people: Lorentz Transformation, Maxwell's equations, Michelson-Morley experiment, ect. These works actually created the postulates which Einstein basically borrowed, i.e. the speed of light is the same for all observers at constant speed no matter the velocity of the observer, the transformations necessary to interpret space/time, ect.. Einstein didn't come up with the concept of relativity - a concept dating back to at least Galileo Galilei. Even Einstein's thought experiment of a rocket or elevator in space is just a reinterpretation of Galileo's "moving ship on a calm sea" thought experiment. Secondly, the formulas for magnetism, electricity and gravity are so profoundly similar, it suggesting that gravity is a force consistent electricity and magnetism. Lastly, the concept of "the fabric" of space and the "warping" of space/time (often diagrammed on a space-time diagram, along with the conical representation of light on such a diagram), to describe gravity as not a force, in my opinion, is almost idiotic. Even as physicists who describe gravity as the warping of space, still work with the concepts of gravitons and photons, and describe both gravity and light as acting through waves.

So when is Lex interviewing Terrence Howard? 😂

the fundamental difference between space and time can be observed in the theory of relativity in several ways. e.g. in terms of the signs (see: Minkowski metric), but also in the fact that while in the case of space the straight line (geodesic line, i.e. inertial motion) between two points gives the shortest path, in the case of time the straight line (geodesic line, i.e. inertial motion) between two events gives the longest time, but all this is also analogous to the fact that in both special and special relativity we are talking about spacetime rotations (in special relativity this is given by the Lorentz-symmetry or Lorentz-invariance, while in general relativity this is given by rotation of the light cone due to the gravity described by Einstein's field equations), i.e. a kind of antisymmetric relation between space and time, and this is exactly what is reflected by the kinetic and gravitational time dilations.

If all velocity is relative, how can anything be said to be moving at any particular speed?

Sean Carroll reminds me of the dad in Happiness (1998)

Would we feel an acceleration in time the way we feel an acceleration in space?

Death is a black hole for the soul

Could someone elaborate on why it takes less time when you zig zag from point A to point B?

You can only proof a theory wrong but never right - feynman

I'm not a scientist or a theorist I'm just an average human being I love math and I love computer coding, creating formulas. Hypothesize removing time from the equation and adding an action element instead my mathematical equations for a computer lined up and it was printing the code mathematically correct does anyone understand this

I think this gent is the bass-vocal in rockapella

Well stated.

Matter(s)=matter matters

The information problem doesn't seem terribly difficult. Quantum information is easy to conserve if it is fungible. I might never get my exact test particle back, but I can find one that has my particle's charge, and maybe another with its spin, etc. The only problem that might arise is if, somehow, the sum of the radiation is not equal to the sum of everything it ate. This has been neither predicted nor observed, and is unlikely to ever be. I think we're fine.

Who created the universe and why?

Its good to 9.45- i sort of got it, then im out can someone explain the explanation

curious, how much information does a black hole contain, just epically compressed.. The univers's "HardDrives"

electricity to gravity, hi Terrence!!

Black holes fix entropy, no? Are things becoming more or less ordered as they cross the event horizon of a black hole?

the "information paradox of black holes" is fundamentally wrong. to be honest, I have never understood why is it an issue at all. information can be erased, even in quantum physics. just think of the extended versions of the double slit experiment (e.g. the quantum eraser or the delayed-choice quantum eraser experiments). not to mention that Landauer's Principle is perfectly consistent with black holes and Hawking's radiation: Landauer's principle suggests that erasing information always generates a minimum amount of heat, indicating a link between information and thermodynamics. this implies that even perfect erasure might have subtle consequences. and this is what we see as Hawking's radiation. there is no paradox here.

The earth isn’t flat The Universe is Flat I guessed

I think Einstein’s greatest accomplishment was laying down the theoretical foundations of Lasers. Which he did in 1917

Imagine how different the world could be if Einstein didn't make it out of Germany

seems legit

Maybe we r all living in a simulation, and the black hole is the program's equivalent of the PC trash bin. And EH is emptying the bin. And the reason why black holes are so dense is bc of all the deleted files being accumulated inside the simulation's trash bin before it being emptied

Nice shirt

So a black holes emit radiation?

I knew it. Einstein gets too much credit for ideas he gleaned from his teacher, wife and others. Sad. He needs to return the Nobel Prize.

there is no smallest jar

Time is law in motion...to be more exact...time is gods law in motion...all laws are created and have purpose and intention...they can't be broken..they can only be discovered. Time is those laws working...time ceases when laws cease....when a living creature dies,, all laws have ceased for that person..

They should make a movie about Herman Minkowski, then he might get the public profile he deserves.

A black hole is a star turned inside out.

11:10 I’m so lost

How does quantum compare to corpuscle theory?

String theory doesnt work

How quantum gravity works can be seen using HYBRID gyroscopes With the help of the “HYBRID gyroscope” you can make scientific discoveries; in astronomy, astrophysics, cosmology, higher theoretical physics,... I am writing to you with a proposal for the joint invention of a HYBRID gyroscope from non-circular, TWO coils with a new type of optical fiber with a “hollow core photonic-substituted vacuum zone or (NANF)” where - the light travels 48000 meters in each arm, while it does not exceed the parameters 40/40/40 cm, and the weight is 4 kg. Manufacturers of “Fiber Optic Gyroscopes” can produce HYBRID gyroscopes for educational and practical use in schools and higher education institutions. Einstein dreamed of measuring the speed of a train, an airplane - through the Michelson-Morley experiment of 1881/2024, and only then would the experiment be more than 70% complete. This can be done using a fiber optic HYBRID gyroscope. Based on the completion of more than 70% of Michelson's experiment, the following postulates can be proven: Light is an ordered vibration of gravitational quanta, and dominant gravitational fields adjust the speed of light in a vacuum. (We are not looking for ether, we will see the work of gravitational quanta) The result is a «theory of everything» in a simple teaching device and a new tape measure for measuring the universe.

Time is objective reality other than that it doesn't exist. There is movement, movement is affected by gravity.

I don't know why I don't like lex! Maybe it's the outfit

I know that Lex Friedman was born in Moscow, but he totally looks like a love child between Joe Rogan and Belinda Carlisle. . . . Maybe Joe was at a GoGo's concert in 1983. 😅

Shout out to Minkowski.

Special relativity and general relativity are completely separate theories with no relation to each other. Comparing their origins, special relativity is Einstein's consolidation of decades of advancements in electromagnetism under the concept of the principle of relativity. In contrast, general relativity is almost entirely a product of Einstein's original imagination. However, general relativity was already debunked by Max Born at its starting point, the equivalence principle, proving it to be a flawed theory. The so-called evidence for general relativity can be fully explained by special relativity alone, as you can see by searching "Relativistic Universe and Forces." Einstein's general theory of relativity was just another failure created on a sofa. I hope there will be no more people misleading the world with general relativity.

This guy is no brian greene

Are we not practicing black hole theories by stirring a cup of coffee with a spoon when mixing with sugar or milk or by cooking. Stirred,filtered and released.🤔 just asking?🤷🏾‍♀️

Mass creates a gap in spacetime, ez fucking definition

Carrol has the voice of a hairstylist, a male ballet dancer, or a catholic priest if you get my drift

Minkowski was a nut who deserves no praise. Recognition for coming up with spacetime as a concept, yes, but he was a zealot who hallucinated that space and time would forever be forgotten. That’s crackpot territory. Spacetime is a metric, nothing else. It isn’t real.

He claims Einstein didn’t understand black holes. Yes he did. He doubted that space could contain upwards of infinite density in a small area. Which by the way is still not proven.

That was a pretty un-extraordinary explanation of general relativity. Perhaps good for people who already understand it.

I'm still with the doubters on Minkowski's contribution. Even in an outlandish world where 3D space emerges from some kind of cosmic brain or infinite-dimensional computerverse, I don't see how spacetime can be anything more than a mathematical convenience. I would put it up there with string theory in the category of physics being hijacked by mathematicians.

Bruh the other side is cool

Came here to obseve the armchair Einstein's 😜

He can't even explain basic biology so what the hell

@deanodebo nah bro 🤣 close your eyes and it's Howard Stern 😂

You guys obviously never heard about terryology

Sean Carroll keeps talking with a strange inflection in his voice And will not any seek any further insight He needs to get high

Postmodern sophistry

An entire career based on fraud.

How can Sean understand relativity, he doesn’t even understand gender

I cringe everytime I hear the words "space/time"

That's still not how you pronounce "Minkowski" correctly.

😂😂😂👌 so anyone can write a book now?