Placeholder Image

Subtitles section Play video

  • I read one science fiction story where the bad guy gets thrown into a black hole and he screams in fact he screams forever.

  • I'm dr Michio Kaku professor of theoretical physics and best selling author of the God equation and I'm here today to answer your questions on twitter.

  • This is physics support cal is not a cow ask y'all, why do atoms want to bond so much?

  • Why don't they just stay single?

  • You aren't missing anything Adams want to bond together.

  • That's why we have molecules.

  • That's why we have people D.

  • N.

  • A.

  • R.

  • Universes based on atoms which like to bond with each other, the electron vibrates back and forth binding them together.

  • And that's why we have molecules.

  • That's why we have you you are a consequence of the fact that electrons are shared between different atoms.

  • Using the laws of the quantum theory.

  • Debra morrow Zach asked the question, What's your favorite law of physics?

  • Mine is momentum conservation.

  • Well my favorite law of physics is the equivalence of matter and energy.

  • Einstein's equation E equals M.

  • C.

  • Squared.

  • This is why the sun shines.

  • It's why the stars twinkle, it's what lights up the universe.

  • We like to think that matter and energy are totally different things.

  • How can a rock turn into energy?

  • However if that rock is uranium and that energy is the fireball of the nuclear bomb, you realize that matter and energy or two sides of the same coin.

  • Matter energy is one unit and they can flip into each other under certain circumstances like in the heart of a star Sean Harris at info sec Hotspot asked, does anyone know of people like Michiko Kakutani that can explain string theory like he does for people like me and I'm not a genius.

  • Well I am Mikio Kaku and I'd be glad to answer that question.

  • First of all, most textbooks say that an electron is a dot, particles that we see in our atom smashers are dots.

  • But if I had a super microscope, I can see that that dot is actually a rubber band.

  • From a distance, this rubber band looks like a dot close up.

  • You see that it's a vibrating string.

  • Now this rubber band can vibrate in many different modes.

  • Each mode can be called a particle.

  • So for example, this might be an electron, but if you total it in a different way, it becomes a quirk.

  • And if you toilet this way you have to give it a different name.

  • We call it a neutrino Now, how many ways can one string vibrate?

  • The answer is obvious.

  • An infinite number of vibrations on the same string.

  • And so we think that all the subatomic particles of the universe, the corks, the neutrinos, the mesons, the protons and neutrons.

  • There's a galaxy of these particles, there's nothing but musical notes on a tiny rubber band.

  • A rubber band so small that it looks like a dot.

  • So what is physics that we have to struggle with In high school physics is the harmonies.

  • The harmonies of vibrating strings.

  • Physics tells us how these vibrations move with its chemistry.

  • Chemistry is when these strings bump into each other and form molecules Alex add cure asks kong asked what is a quirk?

  • What is OMG Yeah it's a oh my God, we think that inside the proton there are three quirks, subatomic particles that make up the protons and neutrons which in turn make up our universe.

  • Here's a question from Rick at Sojourner 99.

  • We live in four dimensions but can see three, how many dimensions are there?

  • Einstein says we live in a four dimensional world.

  • We can go forward, backward, left, right up down and the fourth dimension is time.

  • But now we're beyond Einstein And we have to go beyond four dimensions to perhaps let's say 10-11 dimensions.

  • But where are these other dimensions?

  • We think they have curled up there so small that you cannot enter them.

  • But perhaps we can feel their effects.

  • And where is this other dimension?

  • It is off the plane of your universe.

  • Perhaps a parallel universe hovering right above your universe in another dimension, that we cannot see your touch.

  • But perhaps there's a gateway connecting them.

  • That gateway is the wormhole, it was Einstein himself in 1935 who introduced the concept of a wormhole, a gateway between higher dimensional universes.

  • Well the next question comes from J mo Zach who asked the quantum universe?

  • Was Einstein wrong about his theory of relativity.

  • Yes and no.

  • There's a famous quote where Einstein said the more successful the quantum theory gets the sillier it looks, he thought that atomic physics that is quantum mechanics was incomplete when the Nobel prize was given to people like Heisenberg, he said yes, give them the Nobel prize, they're onto something.

  • And so Weinstein had reservations about the quantum theory as the final theory.

  • He thought there had to be a higher theory, a theory even beyond the quantum theory.

  • So Einstein was not totally incorrect.

  • Obi would shana lang asked what is the God equation?

  • Well, Einstein spent the last 30 years of his life Chasing after the God equation.

  • An equation perhaps no more than 1" long.

  • That would allow us to quote read the mind of God, a theory that would unite the two branches of physics.

  • On one hand we have the theory of the big general relativity, black holes, big bangs and the theory of the small quantum theory.

  • Atomic physics.

  • How can you unite these two into one theory at the present time.

  • These two theories hate each other.

  • They're based on different mathematics, different principles, different concepts.

  • And yet we believe in our heart of Hearts.

  • There has to be a master theory out there.

  • The Holy grail of physics and that we think is the God equation.

  • The leading and only candidate for that is string theory.

  • And by the way, if you ever find the God equation, Tell me first, we'll split the Nobel prize money together, you and me, here's a question from Princeton University Press and that is who is your favorite physicists?

  • 46.2% said that Einstein was their favorite physicist.

  • 53.8% thought that Richard Feynman was their favorite physicist.

  • My favorite physicist is Isaac Newton.

  • He asked the question for the ages if an apple falls, does the moon also fall?

  • And he realized that he didn't have the mathematics to calculate a falling moon.

  • So what did he do?

  • He invented his own mathematics called calculus and the theory was one of the greatest theories of all time.

  • Newton's law of gravity and so during the black plague of 16 66 one of the greatest minds in history went from superstition and thrust us into the age of mechanics.

  • The Industrial revolution, he changed world history, You can't beat that.

  • Einstein is way up there, so is Richard Feinman, but Isaac Newton tops them all.

  • The next question comes from Hassan baba ji who asked can light bend around corners if yes or no, give one reason, yes.

  • Light can bend around corners.

  • In fact, that's why we have glass inside your glasses.

  • When light goes into glass, it slows down slightly because it slows down, it deviates from a straight line and that's why we have your glasses telescopes microscopes because glass bends light also gravity can bend light as Einstein showed us.

  • And we can actually see the bending of light as it goes around a galaxy.

  • Then the next question is can you bend light completely around an object?

  • So the object becomes invisible?

  • And the answer is yes.

  • It's well within the laws of physics that if you could govern the atomic structure of glass then light would bend in a way such that it would completely go around an object.

  • So anything inside that object becomes invisible.

  • One day we will build a meta material out of nanotechnology that will bend visible light so that anything inside that capsule will become invisible.

  • Harry potter.

  • Watch out Boxing fan 2000 and one asks, how do black holes distort time?

  • And what the hell does that mean?

  • Time does not beat uniformly throughout the universe, clocks on the moon beat a little bit faster than clocks on the planet Earth on jupiter clock's beat slower than on the planet Earth.

  • The heavier the planet the slower time beats.

  • This means that in a star like the sun, time beats even slower and the ultimate star of course, is the black hole, the remnants of a dying star, we think that at the very center of the black hole, time stops.

  • What does that mean?

  • If you were to fall into a black hole from your point of view, it would take perhaps a few minutes let's say, to fall through a black hole depending upon where you started from your watch says that you went right through to the center of the black hole, but from outside, somebody with a telescope looking at you from outer space would see you frozen in time, slowly going into the black hole.

  • Because time beats at a different rate from the outside and the inside.

  • Get your head around this time can beat at different rates at different points in the universe.

  • Shelby asked like how are black holes and infinite density even possible?

  • Like how does something get so dense that it collapses on itself?

  • I want to know, we know that if I take a gigantic star or galaxy and compress it, its gravity is so great that nothing known to science can escape the clutches of gravity so light itself is trapped by the black hole.

  • And according to textbooks, it collapses to a point of infinite density.

  • Let's be real about this.

  • There's no such thing as infinite density.

  • We just say that in textbooks because we don't know what happens when a star collapses into a tiny dot.

  • Infinite density is a shorthand of saying, I don't know, we really don't know what happens at the very center of a black hole.

  • If you do the mathematics very carefully, you realize that the black hole is spinning and spinning stars collapse to a ring.

  • They don't collapse to a dot at all.

  • And if you fall through the ring.

  • The mathematics says that you fall not just to the ring, but you fall to the other side to a parallel universe.

  • That is on the other side of a black hole, there's a white hole.

  • Everything that falls in gets blown up.

  • The other end of the village celeb at the village celeb, Here's a question for physics people only I was sitting in the backseat of a bus which was going at 120 km/h, a fly rose from my shoulder and flew right up front and landed on the driver's.

  • So does it mean the fly was going faster than the bus?

  • Let's let Newton answer this question.

  • And that is velocities can add.

  • If you are a bystander looking at the bus and the fly from outside, you would say yes, the velocity of the fly is the velocity of the bus, plus the velocity of the fly inside the bus velocities can add.

  • Now, of course, if you're inside the bus, the fly seems to go at a very slow rate.

  • If the bus is really a rocket ship traveling near the speed of light and a fly flies inside the rocket ship, apparently breaking the light barrier, How is that possible?

  • Well, Einstein would say that you cannot add velocities in relativity, The fly cannot break the light barrier, no matter how fast that rocket is moving, no matter how fast that fly is moving, you cannot go faster than the speed of light.

  • Newtonian physics is wrong.

  • That means that the two velocities have to be adjusted because of the fact that time inside the rocket has slowed down.

  • Now, this is amazing!

  • But it works.

  • And this has been measured repeatedly with our particle accelerators and our experiments, David H ap high Well asked this question, What is dark matter cannot be touched?

  • Is it dangerous?

  • Most of the universe is made out of dark matter.

  • Dark matter surrounds the Milky Way galaxy.

  • If it wasn't for dark matter in the Milky Way galaxy would have spun out of control and the Earth would be flung into out of space, can it be touched?

  • Well, no, because it would filter right through your fingertips, right through the atoms of your body.

  • Is it dangerous?

  • No, because it doesn't interact with us.

  • And then here's the big question, what is it?

  • There's a Nobel prize out there, waiting for that person who can figure out what dark matter is, he said ticky tack asked what is the difference between experimental physics and theoretical physics?

  • Experimental physics engages in reality, it does experiments on things you can touch and feel.

  • Theoretical physics tries to explain how and why that happens.

  • Einstein did not do experiments on light beams.

  • He did not do experiments on stars and Galaxies by looking through a telescope.

  • Einstein worked with a pencil and paper that's called theoretical physics and the heavy lifting was done by experimentalists who built the particle accelerators, the telescopes and the devices that allowed us to probe into the center of stars and Galaxies.

  • John H asked the question for physicists is adding a cape to your superhero const oum enhance your flying abilities.

  • I wish that there was a magic cape that we can suddenly put on and soar like superman.

  • It doesn't work that way.

  • Birds fly, not because they flap their wings.