Science Matters with Lawrence Krauss: dark matter, Neanderthal DNA, high temperature records

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Arizona State University physicist Lawrence Krauss joins Ted to discuss the latest science news, including dark matter, Neanderthal DNA and high temperature records.

TED SIMONS: TIME AGAIN FOR OUR REGULAR VISIT WITH ONE OF THE BEST KNOWN PHYSICISTS IN THE WORLD, ASU'S LAWRENCE KRAUSS. TONIGHT GLOBAL WARMING AND SOMETHING OUT OF NOTHING. HERE NOW IS LAWRENCE KRAUSS. GOOD TO SEE YOU.

KRAUSS: SOMETHING OF OUT OF NOTHING.

TED SIMONS: LOOKING SHARP THERE.

KRAUSS: THANK YOU. I KNOW YOU LIKE TO COMMENT ON MY ATTIRE. I TRY TO -- I'M COLOR BLIND. SO IT'S AN ACCIDENT.

TED SIMONS: WE HAVE SO MUCH TO TALK ABOUT.

KRAUSS: WE DO.

TED SIMONS: LUMPS OF INVISIBLE GAS DETECTED IN THE MILKYWAY LOOKING LIKE LENSES. THIS IS REALLY INTERESTING.

KRAUSS: YOU TALK ABOUT INVISIBLE GAS AND I THINK POLITICS. IT'S REALLY NEAT. THE POINT IS THAT THERE'S BEEN A -- ONE OF THE BIG PROBLEMS WITH UNDERSTANDING HOW MUCH STUFF THERE IS AS WE'VE TALKED ABOUT, MOST OF THE MASS IN THE UNIVERSE IS INVISIBLE. IT'S MADE OF SOMETHING ELSE. THERE'S DARK MATTER. BUT WHEN WE ACTUALLY NOW HOW MUCH NORMAL MATTER THERE IS IN THE UNIVERSE, FROM CALCULATIONS OF THE EARLY UNIVERSE, BUT WE LOOK AT THE STARS AND GAS, WE ONLY SEE ABOUT LESS THAN A THIRD, MAYBE A FIFTH OF ALL THE STUFF -- NORMAL STUFF THAT WE KNOW IS OUT THERE. WHERE IS IT? WHAT THIS NEW EXPERIMENT WAS ABLE TO DO WAS LOOK AT THESE DISTANT OBJECTS CALLED QUASARS AND THEY TWINKLE LIKE STARS, BUT THEY REALLY SHOULDN'T. BUT THE REASON THEY TWINKLE IS THE LIGHT FROM THEM BASICALLY GOES THROUGH MATTER IN OUR GALAXY. THAT MATTER IS CHARGED. AND THAT'S A PLASMA.

TED SIMONS: OKAY.

KRAUSS: AND WHEN LIGHT GOES THROUGH PLASMA, IT KIND OF SLOWS DOWN AND SPEEDS UP DEPENDING UPON THE NATURE OF THE PLASMA. THAT CAUSES AS IT GOES THROUGH LUMPS FOR THE LIGHT TO BE MAGNIFIED OR LENSED EFFECTIVELY. WHAT THIS STUDY WAS ABLE TO DO WAS LOOK AT A SPECIFIC EVENT OF A QUASAR DOING THIS AND REALIZE THERE WERE A LOT OF LUMPS IN OUR GALAXY THAT YOU COULDN'T SEE ANYWAY. THIS IS THE ANDROMEDA GALAXY. THIS ISN'T OUR OWN GALAXY. DO YOU KNOW WHY?

TED SIMONS: WHY?

KRAUSS: BECAUSE WE LIVE IN OUR OWN GALAXY. IT LOOKS A LOT LIKE OUR GALAXY.

TED SIMONS: SURE.

KRAUSS: YOU CAN SEE THE STARS ARE NOT GAS. WHAT WE KNOW AND WHAT OUR THEORIES SUGGEST IS THAT THERE SHOULD BE LOTS OF COLD LUMPS OF MATTER, PERHAPS, THAT ARE INVISIBLE, THAT AREN'T EMITTING LIGHT. WHAT THIS NEW STUDY ALLOWED US TO DO AT THE VERY BEGINNING IS BROUGHT A NEW MECHANISM TO LOOK FOR THESE POTENTIALLY DENSE LUMPS. WE REALLY STILL DON'T KNOW HOW THEY FORM, BUT THIS NEW STUDY SUGGESTS THAT THEY'RE THERE. IT'S THE FIRST STEP IN FINDING OUT WHERE ALL THE NORMAL MATTER IS IN THE UNIVERSE. NOT THE DARK MATTER.

TED SIMONS: LET ME GET THIS STRAIGHT. WE HAVE DARK MATTER, WE HAVE MATTER THAT'S NOT SO DARK. WE KNOW IT AND SEE IT. AND THEN WE'VE GOT WHAT?

KRAUSS: THERE'S DIFFERENT KINDS OF DARK MATTER. THERE'S DARK MATTER AND REALLY DARK MATTER. WHEN WE TALK ABOUT DARK MATTER, WE REALLY MEAN THE STUFF THAT DOMINATES BY A FACTOR OF TEN ALL OF THE MASS OF ALL THE STUFF WE CAN SEE IN OUR GALAXY.

TED SIMONS: YES.

KRAUSS: BUT AS I SAY, IF THE UNIVERSE IS FULL OF SNOWBALLS OR TELEVISION COMMENTATORS OR WHATEVER, THEY DON'T SHINE IN THE DARK ALSO THEY'VE BEEN --

TED SIMONS: WHAT ARE YOU TRYING TO SAY?

KRAUSS: YOU'RE VERY SHINY. OUT IN SPACE, NONE OF US WOULD SHINE. SO WE'RE TRYING TO FIGURE OUT WHERE IS -- WE KNOW HOW MUCH NORMAL STUFF THERE IS, BUT IT'S A FACTOR OF FIVE LESS THAN WHAT WE SEE. SO THERE'S THIS MISSING MATTER. NOT SO MUCH DARK MATTER, BUT MISSING PROTONS AND NEUTRONS THAT WE DON'T KNOW WHERE THEY ARE. THIS ALLOWS US A NEW TEST TO FIND OUT WHERE THERE COULD BE NOT SNOWBALLS BUT ESSENTIALLY LARGE LUMPS OF GAS THAT ARE COLD AND WOULD OTHERWISE BE INVISIBLE. UP UNTIL NOW, WE'VE REALLY NEVER KNOWN WHERE THEY ARE. AND THIS MAY SUGGEST A WAY TO UNDERSTAND IF MAYBE WE CAN UNDERSTAND WHERE ALL THE NORMAL MATTER IS IN THE UNIVERSE. WHICH IS REALLY FIVE TIMES MORE THAN ALL THE MATTER IN STARS AND HOT GAS THAT WE CAN SEE.

TED SIMONS: SO THERE'S STILL SOMETHING TO DISCOVER OUT THERE.

KRAUSS: THERE'S ALWAYS SOMETHING TO DISCOVER. THIS IS NOT AS CRAZY AS DARK MATTER. BUT STILL ITS KIND OF INTERESTING.

TED SIMONS: NOW, SPEAKING OF MISSING, WE HAVEN'T SEEN A NEANDERTHAL AROUND THESE PARTS IN QUITE A WHILE. ARE YOU READY FOR THIS? WE ARE MORE NEANDERTHAL THAN WE THOUGHT.

KRAUSS: VERY GOOD. THAT'S THE WRONG PICTURE. ISN'T THAT DONALD TRUMP'S NATIONAL SECURITY ADVISOR? NO, NO, THAT'S THE KNEE -- NEANDERTHAL.

TED SIMONS: YOU JUST BOWLED RIGHT OVER MY JOKE, BY THE WAY.

KRAUSS: I KNOW I KNOW THAT WAS GOOD BUT I THOUGHT MINE WAS GOOD. AND I CANT WAIT FOR THE LETTERS YOURE GOING TO GET FOR THAT. THIS IS NOT A REAL ONE, BUT ITS AN ARTIST IMPRESSEION. THE INTERESTING THING IS OF COURSE THAT NEANDERTHALS WENT EXTINCT PROBABLY ABOUT 30,000 YEARS AGO OR SO AND HOMO SAPIENS, OF WHICH YOU AND I ARE PRIMARILY, SURVIVED. WE PROBABLY LED TO THEIR EXTINCTION. THE INTERESTING THING IS LIKE OFTEN HAPPENS WHEN DIFFERENT CULTURES MEET, THERE WAS MORE THAN JUST EXTINCTION GOING ON. THERE WAS SOME HANKY-PANKY. IN YOUR DNA, IN MY DNA, IN EVERYONE'S DNA EXCEPT THOSE PEOPLE IN AFRICA, THERE IS SOME NEANDERTHAL DNA.

TED SIMONS: 1 TO 5%, I READ. IS THAT TRUE?

KRAUSS: MICHAEL IS VERY PROUD OF THE FACT THAT HE'S 3% NEANDERTHAL. ALTHOUGH HE SAID HIS WIFE IS A LITTLE BIT MORE. YOU CAN GET A STUDY. YOU CAN SEND IT WITH 23 AND ME OR BIT OF SALIVA AND GET YOUR DNA SEQUENCE TO FIND OUT WHAT PERCENTAGE OF YOU IS NEANDERTHAL. SO THAT'S BEEN KNOWN THAT SOME OF OUR -- THAT OF THOSE GROUPS THAT LEFT AFRICA EARLY ON, EARLY ENOUGH TO ENCOUNTER NEANDERTHAL, THERE'S NEANDERTHAL DNA. THE GROUPS THAT STAYED IN AFRICA DON'T HAVE NEANDERTHAL DNA BECAUSE THEY NEVER ENCOUNTERED THEM. THERE'S BEEN A BIG STUDY, A CROSS CULTURAL STUDY, OF MANY THOUSANDS OF PEOPLE TO LOOK AT NEANDERTHAL DNA. WE ACTUALLY HAD SOMEONE HERE AT ASU WHO HAD ACTUALLY SEQUENCED NEANDERTHAL DNA FROM AN ANCIENT PIECE OF BONE. AND WHAT'S REALLY INTERESTING IS WHEN YOU LOOK AT -- THIS STUDY IS DONE, IS LOOK AT THE POSITION OF SOME OF THE NEANDERTHAL DNA AND DISCOVER THAT IT'S LEFT SOME TRAITS FOR YOU AND I ON THE WHOLE NEGATIVE TRAITS.

TED SIMONS: LIKE MORE IMMUNE SYSTEM MAYBE PROBLEMS THERE.

KRAUSS: IMMUNE SYSTEM. IT ALSO CAUSES REACT TO THE SUN DIFFERENTLY. IT PROBABLY PRODUCES TOO MUCH BLOOD CLOTTING. THE POINT IS THAT AT THE TIME THOSE -- THOSE VARIATIONS WERE PROBABLY USEFUL FOR HUMANS WHEN THEY WERE FIRST ENCOUNTERING NEW THINGS IN EUROPE AND WHAT WAS THEN A VERY COLD CLIMATE. THEY PROBABLY COULD USE THE FACT THAT ENHANCED BLOOD CLOTTING COULD BE USEFUL IF YOU'RE ENCOUNTERING CUTS OR A HARSH ENVIRONMENT. NOW IT BECOMES A NEGATIVE EFFECT. IT MEANS TOO MUCH BLOOD CLOTTING. WHAT AMAZES ME, IT ACTUALLY ALSO IMPACTS APPARENTLY BECAUSE OF WHERE THIS IS LOCATED NEAR VARIOUS OTHER GENES THAT AFFECT COGNITIVE PROCESSES, ADDICTION. THAT NEANDERTHAL DNA CAN MAKE US MORE ADDICTIVE PERSONALITIES.

TED SIMONS: I DON'T KNOW IF I WANT A LOT OF NEANDERTHAL IN ME THEN.

KRAUSS: YOU DON'T HAVE A LOT OF CHOICE, FIRST OF ALL. THESE ARE THINGS THAT WE'RE BEGINNING TO GET EVIDENCE OF, BUT THE POINT IS WE ARE WHAT WE ARE NOW AND WE ARE PART NEANDERTHAL. AND -- BUT WE'RE ALSO PART -- ALL OF THE BEINGS THAT EVER MADE WITH, THERE ARE OTHER -- THERE'S LOTS OF OTHER HOMONID SPECIES THAT ALL MAKE UP US TODAY. WE ARE -- WE ARE OUR HISTORY. AND OUR DNA IS THE HISTORY OF HUMANS THROUGHOUT THE PLANET WHICH IS REALLY WHY IT'S IMPORTANT TO UNDERSTAND THAT EVOLUTION HAPPENED AND IT AFFECTS US. IF WE WANT TO UNDERSTAND OUR BEHAVIOR TODAY, OUR IMMUNE LOGICAL RESPONSES, WE NEED TO UNDERSTAND THE HISTORY AND WE CAN'T PUT OUR HEADS IN THE SAND AND PRETEND IT NEVER HAPPENED.

TED SIMONS: THAT'S AN INTERESTING TOT.

KRAUSS: I'LL LET YOU END WITH THAT.

TED SIMONS: WE'RE NOT OVER YET. EARTH HITS ITS HIGHEST TEMPERATURE ON RECORD IN 2016, WHICH MEANS THREE STRAIGHT YEARS OF THE HIGHEST TEMPERATURES RECORDED ON EARTH?

KRAUSS: OVER THE LAST -- COMPARED TO THE 20th CENTURY. HERE'S ONE OF THE GRAPHS. SO, THE AVERAGE TEMPERATURE CHANGES OVER THE COURSE OF THE YEAR. AND WHAT YOU CAN SEE IS A STEADY MARCH UP FROM THE BOTTOM TO THE TOP AND THE TOP IS 2016. THESE ARE THE -- THE TEMPERATURE ANOMALIES, THE TEMPERATURE COMPARED TO THE AVERAGE TEMPERATURE FROM -- THE AVERAGE TEMPERATURE FROM THE ENTIRE 20th CENTURY.

TED SIMONS: YES.

KRAUSS: YOU CAN SEE THAT THERE'S NOW A DEVIATION AT THE PEAK ALMOST 2 DEGREES. IF YOU AVERAGE THIS OVER THE COURSE OF THE YEAR COMPARED TO THE AVERAGE OVER THE 20th CENTURY, SO THE AVERAGE TEMPERATURE IN THE 20th CENTURY, WE ARE NOW ALMOST 1 DEGREE CELSIUS HIGHER THAN THE AVERAGE. AS YOU POINT OUT, WHAT'S REALLY STRIKING IS THAT THESE -- YOU KNOW, EVERY NOW AND THEN, THERE ARE TEMPERATURE FLUCTUATIONS AND YOU GET A HOTTEST YEAR. IN THE LAST THREE YEARS, IT'S THE THREE HOTTEST YEARS CONSECUTIVELY. SINCE 2000, SEVEN OF THE LAST HOTTEST YEARS. I THINK WE HAVE A VIDEO --

TED SIMONS: I THINK WE DO.

KRAUSS: WELL, THAT'S GREAT. LET'S WATCH THE VIDEO.

TED SIMONS: LET'S -- WHAT ARE WE WATCHING HERE?

KRAUSS: WE'RE WATCHING ANOMALY TEMPERATURE OVER THOSE YEARS AND DIFFERENT POINTS OF THE EARTH. BLUE IS COLD AND RED IS HOT. AND YOU NOTICE STARTING ABOUT 1960 IT BEGINS TO GET REDDER AND REDDER. THIS HAS BEEN SUDDEN. THIS ISN'T SOME GRADUAL CHANGE BETWEEN 1980 AND 2000. THIS IS THE AVERAGE TEMPERATURE COMPARED -- EACH PLACE COMPARED TO WHAT IT WAS OVER THE AVERAGE OF THE 20th CENTURY.

TED SIMONS: LET'S WATCH IT AGAIN.

KRAUSS: SEE IT WAS COOLER THAN AVERAGE IN 1880s, BUT IT DIDN'T START GETTING A LOT HOTTER THAN AVERAGE UNTIL AFTER THE 1940s AS INDUSTRIALIZATION BEGAN TO PICK UP. THEN BOOM, YOU SEE AS WE'VE BEEN EMITTING MORE AND MORE CARBON SINCE 1980s, THIS IS A HUGE EFFECT. THIS ISN'T SOME GRADUAL EFFECT LIKE SOME PEOPLE SAY GRADUAL CHANGES, ICE AGE AND EVERYTHING ELSE. YOU CAN REALLY SEE IT IN THAT IMAGE THAT IN THE LAST 20 YEARS, BOOM, IT'S TAKEN OFF.

TED SIMONS: 17 HOTTEST YEARS ON RECORD. 16 OF THEM SINCE 2000.

KRAUSS: SO TO ARGUE THAT SOMEHOW AS HAS BEEN DONE NOW, ONCE AGAIN, THAT GLOBAL WARMING IS SOMEHOW CONTROVERSIAL. IT'S NOT.

TED SIMONS: AND IT'S NOT A CHINESE PLOT. THE PRESIDENT --

KRAUSS: THE PRESIDENT HAS SAID MANY THINGS THAT ARE WRONG ON A DAILY BASIS. YOU TALKED ABOUT SOME OF THEM EARLIER IN THIS PROGRAM. NOT JUST 16 OF THE 17 HOTTEST YEARS, BUT THIS YEAR WAS -- I FORGET WHAT IT WAS. KOREA, SOMEWHERE, THE HOTTEST TEMPERATURE EVER RECORDED. 129 DEGREES. THESE -- AND PEOPLE ARE TALKING ABOUT THE FACT -- IT WILL HAPPEN. YOU NOTICE WHEN YOU SAW THOSE PICTURES THAT THE TEMPERATURE CHANGES ARE DIFFERENT IN DIFFERENT PARTS OF THE EARTH. IT'S NOT UNIFORM. BUT THERE ARE PLACES ON EARTH WHICH WILL BECOME UNINHABITABLE DURING THE DAY FOR HUMANS. IT WILL JUST BE -- BECAUSE YOU CAN ONLY RELEASE YOUR HEAT AT A CERTAIN RATE AND YOU WON'T BE ABLE TO SWEAT ENOUGH. YOU'LL JUST HAVE TO STAY INDOORS.

TED SIMONS: JUST HAVE TO MOVE.

KRAUSS: IF YOU'RE LUCKY ENOUGH. EXCEPT FOR THE FEW BILLION PEOPLE WHO DON'T HAVE THE MONEY.

TED SIMONS: LAST POINT HERE WE DON'T HAVE TOO MUCH TIME LEFT, NOTHING IS SOMETHING ON THE QUANTUM LEVEL. APPARENTLY NOTHING IS SOMETHING, WHICH CUES I SHOULD SAY A BOOK WRITTEN BY A CERTAIN AUTHOR "A UNIVERSE FROM NOTHING." BASICALLY YOU WROTE IT.

KRAUSS: I DID. AND I TALKED ABOUT THE FACT THAT NOTHING IN MODERN PHYSICS IS VERY DIFFERENT THAN THE NOTHING IN ANCIENT TIMES. BECAUSE OF QUANTUM MECHANICS, NOTHING EMPTY SPACE HAS ALL SORTS OF STUFF GOING ON IN IT IN TERMS OF QUANTUM FLUCTUATIONS. I THINK YOU HAD AN IMAGE GO UP THERE. THE POINT IS HOW CAN YOU MEASURE THOSE FLUCTUATIONS AND EMPTY SPACE? WE'VE ACTUALLY DONE IT FOR A WHILE, BUT THIS IS A NEW EXPERIMENT THAT SENDS A LASER BEAM. IT'S A COHERENT BEAM OF LIGHT. BECAUSE OF QUANTUM FLUCTUATIONS, IT'S NOT EXACTLY-- THE WAVES AREN'T EXACTLY UNIFORM. AND THEN -- AND IF THE WAVES ARE LONG ENOUGH WAVELENGTH, LET'S SAY IT OSCILLATES MAYBE ONCE EVERYONE BILLION OF A SECOND, WHICH IS PROBABLY WAY TOO LONG. THEY SEND ANOTHER LASER BEAM WHOSE LENGTH IS ONLY 1 MILLIONTH OF A BILLIONTH OF A SECOND. QUANTUM FLUCTUATIONS ARE HAPPENING ALL THE TIME, BUT WE CAN ACTUALLY CONTROL THEM BY MANIPULATING QUANTUM FLUCTUATIONS. SO IN CERTAIN REGIONS, WE CAN MAKE THEM SMALLER THAN AVERAGE. THE EFFECT IS TO PUSH THOSE FLUCTUATIONS ELSEWHERE AND MAKE THEM BIGGER THAN AVERAGE.

TED SIMONS: LIKE A BALLOON?

KRAUSS: SORT OF LIKE A BALLOON. AND WE CAN USE THE LIGHT WHERE THE FLUCTUATIONS ARE SMALLER TO MEASURE THINGS PRECISELY. IT'S THAT SQUEEZING. WE CALL THAT SQUEEZING OF THE VACUUM THAT WE USE TO MEASURE GRAVITATIONAL WAVES. YOU CAN'T GET AROUND QUANTUM MECHANICS, BUT YOU CAN SQUEEZE THE BAD STUFF AWAY AND USE THE GOOD STUFF. IN SOME SENSE BY THAT IMAGE, WE CAN SEE THE FLUCTUATIONS OF EMPTY SPACE WHICH TELL YOU THAT NOTHING IS REALLY SOMETHING AND REALLY WORTH WRITING A WHOLE BOOK ABOUT.

TED SIMONS: ENTITLE IT A UNIVERSE FROM NOTHING PERHAPS. THE IDEA OF OBSERVING QUANTUM UNIVERSE WITHOUT ALTERING IT.

KRAUSS: THE POINT IS AS WE KNOW, WHEN YOU MAKE OBSERVATIONS IN QUANTUM MECHANICS, YOU ALTER THINGS. WHAT IS REALLY NICE WITH THESE LASER BEAMS, YOU MEASURE SO THAT THE IMPACT OF THE LASER BEAM, BUT YOU DON'T MEASURE THE FLUCTUATIONS THEMSELVES. SO YOU DON'T ALTER THEM. YOU CAN EFFECTIVELY GET A SHADOW IMAGE OF THOSE FLUCTUATIONS AND SEE THAT LOTS OF NEAT STUFF IS HAPPENING IN EMPTY SPACE. IF WE'RE SMART, WE CAN USE FOR OUR OWN TECHNOLOGY.

TED SIMONS: ALRIGHT, VERY GOOD. I JUST WANT TO SAY TANK YOU.

KRAUSS: THAT MUST HAVE BEEN THE NEANDERTHAL IN YOU.

TED SIMONS: IT WAS. WEDNESDAY ON ARIZONA HORIZON, WE'LL HEAR FROM MARICOPA COUNTY RECORDER ADRIAN FONTES AND WE WILL LEARN ABOUT A PROGRAM DESIGNED TO HELP THOSE WITH EARLY STAGE MEMORY LOSS. THAT'S ON THE NEXT "ARIZONA HORIZON." THAT IS IT FOR NOW. I'M TED SIMONS. THANK YOU SO MUCH FOR JOINING US. YOU HAVE A GREAT EVENING.

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