Science Matters with Lawrence Krauss: gravity waves, new human ancestor

June 14, 2017

Transcript:

TED SIMONS: EACH MONTH WE FOCUS ON THE LATEST SCIENCE NEWS AND INSIGHT FROM A WELL KNOWN PHYSICIST, ASU'S LAWRENCE KRAUSS. TONIGHT, WHAT HAPPENS WHEN TWO BLACK HOLES COLLIDE. HERE HE IS, LAWRENCE KRAUSS.

LAWRENCE KRAUSS: HERE I AM.

TED SIMONS: WE DIDN'T HAVE OUR FANCY OPENER. SOMETIMES WE HAVE IT, SOMETIMES WE DON'T. BEFORE WE TALK ABOUT TWO BLACK HOLES COLLIDING, THIS WAS COLLECTING BY GRAVITATIONAL WAVE VIBRATIONS 3 BILLION LIGHT YEARS AWAY?

LAWRENCE KRAUSS: THIS IS NOT THE FIRST OBSERVATION OF GRAVITATIONAL WAVES, BUT IT'S AMAZING THAT WE CAN DETECT UNDULATIONS FROM SPACE. THE LAST ONE 1.3 BILLION LIGHT YEARS AWAY, THIS ONE 3 BILLION LIGHT YEARS AWAY. TWO BLACK HOLES THAT COLLIDED AND FORMED ONE BIG BLACK HOLE. THE WAVES, RIPPLES IN SPACE HAVE BEEN TRAVELING 3 BILLION YEARS.

TED SIMONS: WE HAVE A VISUAL OF WHAT FOLKS THINK HAPPENED 3 BILLION YEARS AGO. HOW DID THEY GET SO CLOSE?

LAWRENCE KRAUSS: THAT'S WHAT WE ARE TRYING TO FIGURE OUT. WE DIDN'T EVEN KNOW BLACK HOLES THIS MASSIVE EVEN EXISTED. THIS IS ONE BLACK HOLE 30 TIMES THE MASS OF THE SUN, AND ANOTHER 19 TIMES THE MASS OF THE SUN. THEY MUST HAVE FORMED FROM REALLY MASSICE STARS. COMBINING TOGETHER, THEY MUST HAVE FORMED FROM MASSIVE STARS. HOW THEY COULD GET SO CLOSE TOGETHER IS THE OPENING QUESTION. THEY ORBIT TOGETHER AND COLLIDE IN A FRACTION OF A SECTION. THE FINAL MOMENT THEY ARE RELEASED, THEY ORBIT AROUND EACH OTHER A HUNDRED TIMES A SECOND BEFORE THEY COLLIDE. DURING THAT INSTANT, THEY RELEASE GRAVITATIONAL WAVES BECAUSE THERE IS NOTHING OUT THERE BUT A DISTURBANCE. THEY CARRY MORE ENERGY RELEASED THAN BY ALL THE STARS IN THE UNIVERSE. HOW DO BLACK HOLES CONTINUE TO EXIST AND GET SO CLOSE TOGETHER TO ORBIT AND MERGE? THAT'S THE OPEN QUESTION.

TED SIMONS: MORE ENERGY RELEASED THAN ALL OF THE STARS IN THE UNIVERSE.

LAWRENCE KRAUSS: IN THAT FRACTION OF A SECOND.

TED SIMONS: HOW OFTEN DOES THIS HAPPEN?

LAWRENCE KRAUSS: THAT'S WHAT WE ARE TRYING TO FIND OUT. IF YOU THINK ABOUT THE WHOLE UNIVERSE AND YOU SEE A REASONABLE ESTIMATE, THREE EVENTS, PROBABLY TWO BLACK HOLES COLLIDING EVERY TEN MINUTES. WE DIDN'T KNOW THAT FOR SURE. WE DIDN'T KNOW WHETHER THE MASSIVE STARS AFTER THEY EXPLODE, WHAT HAPPENS, THEY GET VERY BIG AND LOSE NUCLEAR FUEL. NORMAL STARS COLLAPSE AND REBOUND IN A SUPER NOVA EXPLOSION. IF THEY ARE MASSIVE ENOUGH, INSTEAD OF REBOUNDING IN A SUPER NOVA, THEY COLLAPSE IN A BLACK HOLE AND DIE OUT. AROUND THE SAME TIME THIS WAS OBSERVED, ASTRONOMERS WERE LOOKING AT ANOTHER STAR GETTING MASSIVE, GETTING BRIGHTER AND BRIGHTER. THEY THOUGHT IT WAS GOING TO BE A MASSIVE EXPLOSION, BUT THEY SAW IT TWINKLE OUT. IT DISAPPEARED. THAT MAY BE BECAUSE IT WAS FORMING A BLACK HOLE.

TED SIMONS: YOU MENTIONED LIGO THIS OBSERVATORY DEAL. CORRECT ME IF I'M WRONG --

LAWRENCE KRAUSS: I WILL.

TED SIMONS: YOU DO. A COUPLE OF MIRRORS JUST KIND OF SHOOK --

LAWRENCE KRAUSS: SORT OF. VERY GENTLY. WE DISCUSSED IT BEFORE. IT'S WORTH REPEATING. TWO ARMS FOUR KILOMETERS LONG APIECE. IF A GRAVITATIONAL WAVE COMES BY ONE ARM GETS SHORTER AND ONE LONGER BECAUSE SPACE WILL CHANGE. THEY HAVE TO LOOK AT THE CHANGE IN ONE ARM COMPARED TO THE OTHER. FOUR KILOMETERS LONG, A CHANGE IN ITS LENGTH 1/1,000 THE SIZE OF A PROTON.

TED SIMONS: HOW DO WE KNOW THE MIRRORS DIDN'T MOVE BECAUSE OF SOMETHING THAT HAPPENED BEFORE?

LAWRENCE KRAUSS: THERE ARE LOTS OF WAYS TO TEST THIS. WE HAVE TWO SETS OF MIRRORS. WE LOOK FOR THE SAME SIGNAL. IF A GRAVITATIONAL WAVE COMES IN AT THE SPEED OF LIGHT, IT WILL TAKE ABOUT 10 MILLISECONDS TO GET FROM WASHINGTON TO LOUISIANA. YOU LOOK FOR THE SAME SIGNAL IN WASHINGTON, LOUISIANA TEN SECONDS APART. WE CAN PREDICT WHAT THE SIGNAL WOULD LOOK LIKE AND WE HAVE A TEMPLATE TO COMPARE THE OBSERVATION TO A PREDICTION. WE KNOW IT'S NOT JUST A RANDOM VIBRATION. THESE ARE PLATINUM EVENTS. THE FIRST AND THIRD ARE PLATINUM. THEY MIMIC WAS GENERAL RELATIVITY PREDICTED. WE CAN USE IT. WE TEST GENERAL ACTIVITY, BUT IT WORKS SO WELL. WE CAN USE IT TO EXPLORE THE PHYSICS OF BLACK HOLES. ONE INTERESTING THING IS, IF THE BLACK HOLES FORM TOGETHER, THEY ARE SPINNING AND ORBITING EACH OTHER AND THE SPINS WOULD BE ALIGNED TO COUPLE EACH OTHER. THESE TWO SEEM TO BE NOT ALIGNED WITH ONE ANOTHER. THAT MEANS ONE BLACK HOLE CAPTURED ANOTHER THAT WAS PRODUCED SOMEWHERE ELSE. WE DON'T YET KNOW HOW YOU CAN GET BLACK HOLES THIS LATE IN THE UNIVERSE WHETHER THEY ARE FORMED TOGETHER OR CLUSTERS IN THE CENTER OF GALAXIES. WE HAVE OPENED A NEW WINDOW ON THE UNIVERSE.

TED SIMONS: EINSTEIN WAS RIGHT, WASN'T HE?

LAWRENCE KRAUSS: HE WAS VERY RIGHT. FRUSTRATINGLY RIGHT.

TED SIMONS: YOU WANT TO PROVE HIM WRONG, DON'T YOU?

LAWRENCE KRAUSS: IN SOME SENSE YOU ALWAYS LEARN SOMETHING NEW. THE CALCULATIONS ARE INCREDIBLY COMPLEX USING SUPER COMPUTERS TO COMPARE THEORIES.

TED SIMONS: WE THOUGHT HOMO SAPIENS 195,000 YEARS OLD. NOW ALL OF A SUDDEN IN MOROCCO, 300,000 YEARS AGO WE ARE FINDING HOMOSAPIANS?

LAWRENCE KRAUSS: PROBABLY. WE HAVE TALKED ABOUT NEW HOMINID SPECIES BEING DISCOVERED. THIS IS IN MOROCCO. A SAMPLE OF JAWBONE THAT WAS ORIGINALLY THOUGHT TO BE 40,000 YEARS OLD. LATER ON PEOPLE REANALYZED AND SAID, 160,000 YEARS OLD. RECENTLY A GROUP LOOKING AT THAT AND DISCOVERING THE SAME SITE IN MOROCCO FOUND ALMOST A COMPLETE SKULL AND TOOLS, FLYNT USED BY THESE STONE AGED CREATURES. YOU CAN DATE THE FLYNT BECAUSE IT WAS WORKED ON BY HUMANS, 280 TO 300,000 YEARS OLD. THE SKULL, IF YOU RECONSTRUCT IT, THE FACE LOOKS A LOT LIKE YOUR FACE. IT'S MORE THAN LIKELY A HOMO SAPIEN.

TED SIMONS: I THINK YOU ARE RIGHT.

LAWRENCE KRAUSS: SEE, IT'S VERY HANDSOME. IT LOOKS MORE LIKE A HOMO SAPIEN THAN OTHERS DISCOVERED. THE BACK PART IS FLATTENED. THIS IS INTERESTING BECAUSE IF IT'S TRUE, IF IT'S REALLY A HOMO SAPIEN, THEN THEY EXISTED IN A VARIETY OF PLACES, ETHIOPIA, MOROCCO AND MAYBE THEY EVOLVED IN DIFFERENT WAYS BECAUSE THE BRAIN WAS NOT LIKE OUR BRAINS WHICH MEANS THAT IT WAS DISTRIBUTED OVER AFRICA SEVERAL HUNDRED THOUSAND YEARS BEFORE THEY WENT TO EUROPE TO KILL THE NEANDERTHALS AND MOVED THROUGHOUT THE WORLD. THE FIRST THING TO POINT OUT, THIS IS A NEW DISCOVERY. IT'S HARD TO INTERPRET. SOME ARE SAYING, MAYBE IT'S NOT A HOMO SAPIEN. IT'S A REALLY INTRIGUING RESULT THAT'S QUITE SUGGESTIVE. WE'RE TRYING TO BUILD A BETTER PICTURE.

TED SIMONS: IT'S A 300,000 - THAT'S A BIG JUMP FROM 195.

LAWRENCE KRAUSS: THERE ARE GENETIC ARGUMENTS THAT SUGGEST THAT HOMO SAPIENS DIVERGE FROM OTHER SPECIES 300,000 YEARS AGO ANYWAY. FROM LOOKING AT GENETIC MARKERS, YOU CAN LOOK BACKWARDS TO SEE WHEN THEY DIVERGED FROM OTHER HOMINID SPECIES. THE LINE IS 300,000 TO 400,000 YEARS. IT'S NOT SURPRISING TO FIND HOMO SAPIENS THAT OLD. IT'S A FASCINATING DISCOVERY TO FIND THEM SO FAR FROM ETHIOPIA. IT'S JUST THE BEGINNING. YOU CAN IMAGINE THEY ARE LUCKY ENOUGH TO FIND THE BONES IN A MINING SITE. CAN YOU IMAGINE WHAT ELSE IS UNDER THE GROUND? AS I OFTEN SAY, IMAGINE HOW HARD IT IS FROM TWO SAMPLES. IF I WAS NEAR HERE IN A BASKETBALL ARENA WATCHING BASKETBALL GAMES, AND THE WHOLE THING COLLAPSED AND THEY FOUND MY SKELETON AND A BASKETBALL PLAYER'S SKULL NEXT TO EACH OTHER, THEY WOULD THINK THEY WERE DIFFERENT SPECIES BECAUSE THEY WOULD BE SO DIFFERENT. SO YOU HAVE TO BE VERY CAREFUL AND CAUTIOUS.

TED SIMONS: I'M GOING TO WRAP IT UP WITH SOMETHING PERSONALLY FOR ME 100% CONFUSING. TITLE FORCES ON FUNCTION OF A PARTICLE WAVE.

LAWRENCE KRAUSS: TELL ME ABOUT IT

TED SIMONS: I JUST DID!

LAWRENCE KRAUSS: THIS IS -- I KNOW YOU LIKE QUANTUM MECHANICS. QUANTUM MECHANICS IS WEIRD BECAUSE WAVES ARE PARTICLE LIKE AND WHAT'S INTERESTING, QUANTUM MECHANICS IS LIKE WASHINGTON, IF YOU CAN'T SEE IT, ANYTHING GOES. PARTICLES CAN BE DOING MANY THINGS AT THE SAME TIME. IF YOU DON'T MEASURE THEM, A SINGLE BEAM CAN BE GOING IN TWO DIFFERENT DIRECTIONS AT THE SAME TIME. UNLESS YOU MEASURE THEM, YOU HAVE TO TAKE INTO ACCOUNT THAT THEY ARE BOTH. WE CAN USE THAT IN THIS IMAGE. WHAT WE HAVE DONE -- NOT ME BUT OTHER PEOPLE, HAVE TAKEN COLD ATOMS AND YOU CAN SHINE LASER LIGHT ON THEM AND CAUSE THE WAVE PART TO SPLIT INTO TWO GROUPS THAT GO DIFFERENT DIRECTIONS. WHEN THEY COME BACK TOGETHER, THEY INTERFERE. THEY SET THE BEAM OF COLD ATOMS FAR ENOUGH APART THAT IF YOU PUT IT NEAR A BIG MASS, YOU CAN MEASURE THE GRAVITY. ON THE WAY THEY FUNCTION DIFFERENTLY. YOU CAN MEASURE THE SPACE USING THE QUANTUM MECHANICS. THE FACT THAT WE CAN DO THAT, WE CAN TAKE PARTICLES AND USE THEIR QUANTUM MECHANICAL PROPERTIES AND MEASURE THE INTERFERENCES TO MEASURE GRAVITY IS AMAZING.

TED SIMONS: WHEN WE SAY THAT, CAN WE SHOW THE VISUAL AGAIN, WHEN YOU SAY THAT AND I LOOK AT THE VISUAL --

LAWRENCE KRAUSS: YOU UNDERSTAND BETTER?

TED SIMONS: IT MAKES IT MORE CONFUSING.

LAWRENCE KRAUSS: YOU HAVE TWO BEAMS SEPARATING THEM INTO PINK AND GREEN. YOU SHINE THE BEAMS ON THOSE IT CAUSES--

TED SIMONS: THE TAILS OF THEM.

LAWRENCE KRAUSS: IT CAUSES EACH OF THEM TO GO IN DIFFERENT DIRECTIONS AND COME BACK TOGETHER AGAIN. LOOKING AT THE INTERSECTION, YOU GET AN INTERFERENCE AND AWAY FUNCTION DIFFERENT FROM THE LOWER ONE THAN THE UPPER ONE. THAT TELLS YOU IT'S A CURVED SPACE.

TED SIMONS: WHAT ABOUT THE TAILS? WHAT ABOUT THOSE RATTLES?

LAWRENCE KRAUSS: THOSE ARE INTERFERENCE PATTERNS. YOU GET PEAKS AND TROUGHS. EVEN THOUGH THEY ARE PARTICLES, THEY ACT LIKE WAVES. IT MEANS WE CAN MANIPULATE QUANTUM MECHANICS BY COOLING ATOMS TO MILLIONS OF DEGREES ABOVE ABOSLUTE ZERO TO EXPLORE QUANTUM MECHANIC PROPERTIES. WE USE THE SAME TECHNOLOGIES TO ALLOW US TO DO CALCULATIONS MUCH FASTER. THE WHOLE SET OF TECHNOLOGY IS AGAIN AN EMERGING FIELD THAT WILL BECOME IN MANY WAYS THE TECHNOLOGY OF THE 21ST CENTURY.

TED SIMONS: GOOD STUFF. I COULD FOLLOW THAT.

LAWRENCE KRAUSS: THEN I'M SURE EVERYONE ELSE COULD TOO.

TED SIMONS: GOOD TO SEE YOU. UP NEXT, WE TALK ABOUT GETTING MORE ARIZONANS INTO COLLEGE.