Dr. Brian is brilliant as always, but props to Dr. Chiara for being equally as brilliant. Great educators. The universe is a lot more beautiful because of people like you. Thank you for all your contributions to Mankind. Wishing the whole team more success.
Thank you Dr Greene! I'm just a regular guy who works in a factory, but the nature of reality is very important to me. Thank you for bringing this data and these ideas to people like me.
We are all just regular people trying to understand shit. Job and social status are not that important for the desire to understand these things in my opinion.
The concept of NEUTRON STARS - of all things - being "squishy" boggles my mind as much as learning that a teaspoon of neutron star would weigh like 10 million tons.
"What were you doing for 15 years??" LOL this was my question as soon as the timeframe was mentioned 😂. Taking the time to collect all this good data is pure dedication. Thanks for your work.
Thank you Brian, your team and guests for another wonderful session. I am very much just a layman but I have always thoroughly enjoyed your work and I appreciate the work and effort to keep the broader public informed on the cutting edge of subjects in science in general, especially the physics and cosmological topics. Thank you from the UK.
How wonderfully blessed we are to live among such brilliant Minds who continually and doggedly peel back the many layers of secrets our Universe holds. Stunningly impressive and inspirational work. Thank you Prof. Greene for introducing these amazing people to us. Chiara is a very talented science communicator.
Also, how counter-intuitive is it to hear something as compact as a neutron star be described as 'squishy', but that black holes which are essentially extreme gravitational wells in spacetime, be described as being ' hard ', and not deforming under these extreme conditions. Mindblowing stuff.
Thank you Dr. Greene for taking us on yet another cosmological ride full of knowledge, awareness and ecstacy 🙏 you know i can never consume enough of your videos, they're just too short. Thank you for raising the quest in me to ask questions to myself about myself. Hope you keep these deep physical knowledge of cosmology keep coming in the future 🙏
Brian greene is one of my favourite physicist and I eagerly wait for his videos as they give us an edge to think over the research related ideas ...He is one of the best and amazing speakers.
Professor Greene it is such a pleasure to watch these. I will never waste a minute of my life thinking this world is simple and boring. Society has come between greatness and I for far too long. Here I come.
I've been reading Brian Greene for don't know how long, but _seeing_ him visibly enjoy the same topics that intrigue us, too, is another matter, a _light_ matter.
The online and upcoming new powerful tools and techniques will allow us to progress in the cosmos understanding. Amazing and unthinkable discoveries awaiting.
Finally the shows continue again. Could we have an indepth episode around the possibility of black holes actually creating universe's within as the laws and the way it wouldcappear to work make sense minus a few human errors.
Great show. I have Physics degree so understand the maths behind it. However, great to see this discussed in open forum for the general public, most people are interested in space stuff. PS Good to see physicists that seem natural with a sense of humour PPS The thought that we may soon detect gravitational waves from big bang ir superstrings thrills me
Fabulous listening to you guys. I follow ESA on Facebook, if you don't, please do as you get all the info for and from the missions. I'm obsessed with dark matter and dark energy so bring it on Brian!
Thank you! Appreciate your brilliant Narration surge of expansion etc.. Gives me a window of insight on your cosmology explorations with your telescopic lenses with its varied tech progress! To answer "Why"? ❤❤❤for sciences matters Thank you!😮
32:14 One of my puppies did that tonight, but he also snapped his leash. So, naturally, I'm wondering whether or not spacetime or its fields could snap from the tension on them? Would they form new loops of the string, vibrating at new relative frequencies and so as different particles?
In a corner of his house, Dr Brian Greene hosts the most coolest physics forum there is! I only have one question as the result of watching this gravitational discussion.. Is a black hole made of dark energy/matter?
Can't wait to see the cosmic gravitational wave background in relation to the cosmic microwave background. Wow. Thanks guys for discovering more about gravity. And now we have the ability to see the universe in the way a bat does.
The evolution of dark matter and matter looks so much like how our brain’s neural network forms does it not? Isn’t that remarkable? I just find it so beautifully ironic, almost as it is intended. Patterns like this are everywhere in nature. The universe is no exception. What a wonderful time to be able to discover these things … we are the pioneers for future generations.
Roger Penrose suggested that in our universe there could be Gravitational Waves from Black holes coming from a previous universe in the very far past. If such a previous universe Existed and if Black hole morgens emitted gravitational waves: could these waves be measured with the Neutron Star method? Or would such waves Still be beyond our reach and not a Potential source?
As a layman in this area ... I understand that two orbiting masses should spin arround each other forever ... but they loose velocity and collide and one way they loose that energy is by dispersing gravitational waves. Is this correct? If so it then implies that energy is required to change the state of gravity. It also implies that there's a direct similarity between electromagnetic waves and gravitational waves. It's just at a different scale.
Great a woman!!! I started in Berlin with science in the Otto-Hahn Bau in Berlin, Germany! Lise Meitner!!! And sincenI have been a teenager Marie Curie was my role Model! Than came Heisenberg and others. I studied Biology, than switched to medical research, cancer research and from 2001-2008 and Harvard, first Postdoc and than became even a faculty member at Harvard Medical school
Why only two arms for LIGO? Wouldn't a “3D mesh” of arms give us much better detail? Surely we could separate out the direction and magnitude of the waves with an array of detectors.
A solar system sized black hole.. orbiting another black hole the size of our solar system... That's some serious imagery. Even though we don't know why gravity is. I love you world science festival
The moment a particle is a wave; it has to be a conscious wave! Gravity is the conscious attraction among waves to create the illusion of particles, and our experience-able Universe. Max Planck states: "Consciousness is fundamental and matter is derived from Consciousness". Life is the Infinite Consciousness, experiencing the Infinite Possibilities, Infinitely. We are "It", experiencing our infinite possibilities in our finite moment. Our job is to make it interesting!
... or at the _very_ least we start looking/thinking in these other ways, or directions. ive become more and more disappointed over the last 20...30 'odd years because of the unwillingness to even think in these... other ways. admittedly its taken me most of that same time to open up to them, I was very 'science only/has all the answers' based and unwilling to examine these "so called" fringes but, if honest they are just other ideas /points of view and in many cases being thought of, or believed in for much longer. i sometimes wonder if this build up of "dark matter /energy" (2 other words for... we don't know) is the 'manifestation' of the enormous amount of information we have generated in the last few hundred years painted onto higher dimensional 'shaped' objects that we can only see/interact with the equivalent of a shadow, or reflection of our 'every day' objects a reflection/shadow of something having vast amounts of near massless, but seemingly correct information about the objects but only when viewed in a very certain way like slices of the 3d object does when viewing in flatland/lower dimensions... I hope that makes some sense 😊
Is it possible that there is a space that is preexisting that our universe is expanding to fill, and what looks like a force pushing out and expanding the universe is actually a vacuum pulling out?
While I am sure there is plenty of room at he L2 point for the instruments parked there now and planned in the next few decades, is there any risk of cluttering it up? Or is the L2 point sufficiently orbitally unstable that instruments that fall into disuse will drift out of the region?
I've been posting this story for a while, now. Is it possible it's related to gravitational waves? Time is fascinating. I worked the subway stations for nearly 10 years. From one end of the city to the other. Every so often I would notice the city would be saying that, "Today just flew by" or "The day was just dragging along." How can an entire city, with no interaction with each other until they used the subway, complain about the same time paradox unless it was effected by it? Maybe a time distorted bubble the earth passes through in its revolution around the sun. Maybe random waves of time distortion hitting the earth? Maybe they're given off by the sun. Maybe they're from outside our Terran system and reach us in intervals. ???? Ti-i-i-ime, is on my side. Yes, it is! If you can think of a better way to do a blind survey of an entire city, in the small window of opportunity, I'm all in. Until then, I invite you to spend a couple years in the subways, during rush hour and you'll see for yourself. Just listen as an entire city gets off of work and gets out of school. You'll see it's more than a, "coincidence of circumstances."
that's an interesting observation and as i understand it, yes, like a boat riding the waves, a large wave (or smaller boat) has to ride it as a whole up one side then down the other
Very eloquent presentation! Although i would be curious mister Greene to hear your real point of view on a foundation that it’s main goal is to blur the laypeople about a non existing relation between two incompatible identities…
Dr. Greene, if I could suggest a topic, it would be the origin of the Solar system and how similar or rather, different from exo solar systems it seems to be, thank you!
Hi Guys; what's the force carrier for the G wave and/or the medium transferring the wave energy across space? Please disregard the headlights and get out of the roadway.
I've always been curious about the structure of the universe, like if we could map out the universe in an I instance of time, mapping light years. What would that look like
In a tug of war game, both of team members are on the same ground (same plane). What about tug of war in our solar system? Are their orbits on the same plane or changing time to time?
So gravitational waves are not effected by time dilation? When two BHs are merged, time is slowed down relative to the earth. Like a movie "Interstellar", one hour on the planet next the BH was 7 years on the earth relatively. So say it took 2 seconds at the last moment of the merge and we here on Earth detected it. It's still the same 2 seconds? No time delation? Would that mean there's no "red-shift' because of the expansion of the universe, spacetime?
I'm confused. Much of this discussion centers on the idea of demonstrating that gravitational waves exist - in the first place. But didn't Taylor and Hulse already demonstrate that in 1974 using pulsar timing measurements at Arecibo with sufficient credibility to win the Nobel Prize in 1993 ?
Is it a gravitational wave if the object first comes closer and then goes further away. I observe from afar, does the strength of gravity vary? A normal thing like the tide in the phenomenon?
If dark energy were moving through the universe like heat through water, mass should be brought together like foam on the surface. That would require dark energy to move faster than light, maybe with continued influence from the cosmic origin on mass. Or for a strange geometry in time space
I still have no idea what cosmic strings are ^^ I wished he would have used more a mathematical description. Now, I am not sure if he talks about topology or geometry or fields or if it just was a nice image.
Is there a distance close enough to earth to where we would feel these gravitational waves but far enough away not to destroy the earth??? If you could hypothetically move the two blackholes.
In my view the phenomenon of gravitational waves indicates that space time is compressible. This indicates that space time has a variable density. I would expect that density to increase in the presence of baryonic matter so that a large amount of mass will bend the path of light in the same way that light passing through air and entering water is bent. I think that Einstein used the wrong terminology to describe this effect: mass does not curve space but rather compresses space. This may indicate that matter doesn’t exist within space but rather it displaces space. Therefore the larger a mass is the more dense the adjacent space will be.
Dr. Brian is brilliant as always, but props to Dr. Chiara for being equally as brilliant. Great educators. The universe is a lot more beautiful because of people like you. Thank you for all your contributions to Mankind. Wishing the whole team more success.
My appreciation and gratitude to you Dr Brian Greene can only be measured in astronomical scales ; thank you again🙏🏽💐
Chiara Mingarelli a great science communicator! Energetic, funny, relaxed and explains complec things such at can be understood bij non experts.
Thank you Dr Greene! I'm just a regular guy who works in a factory, but the nature of reality is very important to me. Thank you for bringing this data and these ideas to people like me.
We are all just regular people trying to understand shit. Job and social status are not that important for the desire to understand these things in my opinion.
The concept of NEUTRON STARS - of all things - being "squishy" boggles my mind as much as learning that a teaspoon of neutron star would weigh like 10 million tons.
Dr.brian Greene is the inspiration and one of the revolutionaries of science field who is increasing the awareness about importance of science.
"What were you doing for 15 years??"
LOL this was my question as soon as the timeframe was mentioned 😂. Taking the time to collect all this good data is pure dedication. Thanks for your work.
Thank you Brian, your team and guests for another wonderful session. I am very much just a layman but I have always thoroughly enjoyed your work and I appreciate the work and effort to keep the broader public informed on the cutting edge of subjects in science in general, especially the physics and cosmological topics.
Thank you from the UK.
Gosh, Brian has to be the hardest working physicist. Bravo ❤
Thank you Dr. Greene for being there for us during those Covid days - this does take me back. Let’s keep this tradition.
Awesome, another S.F. event! Thank you for your hard work and sharing resource.
How wonderfully blessed we are to live among such brilliant Minds
who continually and doggedly peel back the many layers of secrets
our Universe holds. Stunningly impressive and inspirational work.
Thank you Prof. Greene for introducing these amazing people to us.
Chiara is a very talented science communicator.
Also, how counter-intuitive is it to hear something as compact as
a neutron star be described as 'squishy', but that black holes
which are essentially extreme gravitational wells in spacetime, be described
as being ' hard ', and not deforming under these extreme conditions.
Mindblowing stuff.
Chiara's sound effects are A+.
Dr Chiara is amazing, to be so elegant, clever and explain things so well.
Excellent interviews, so informative. Dr. Greene brings out the best in his guests.
Wow! What great conversations with Chiara and Jason to help us lay people keep up with the amazing research projects to better understand the cosmos.
Thank you for a wonderful presentation with excellent guests!
Wow! They saw Omm in gravitational waves! ❤
And equlid is an amazing achievement of mankind
Thank you sir for those two interviews 🙏
Thank you Dr. Greene for taking us on yet another cosmological ride full of knowledge, awareness and ecstacy 🙏 you know i can never consume enough of your videos, they're just too short. Thank you for raising the quest in me to ask questions to myself about myself. Hope you keep these deep physical knowledge of cosmology keep coming in the future 🙏
Wow. It's back. Love these long dialog discussions. More please with guests love it
❤
Love you Vera Ruben❤
Brian greene is one of my favourite physicist and I eagerly wait for his videos as they give us an edge to think over the research related ideas ...He is one of the best and amazing speakers.
Congrats🎉
Happy day, happy day! Thank you Dr. Greene!
Professor Greene it is such a pleasure to watch these. I will never waste a minute of my life thinking this world is simple and boring. Society has come between greatness and I for far too long. Here I come.
I've been reading Brian Greene for don't know how long, but _seeing_ him visibly enjoy the same topics that intrigue us, too, is another matter, a _light_ matter.
It’s enjoyable to see how excited they are discussing these topics. Fascinating stuff when you are in the right frame of mind to truly listen.
The online and upcoming new powerful tools and techniques will allow us to progress in the cosmos understanding. Amazing and unthinkable discoveries awaiting.
Brian Greene - communicator extraordinaire!
Brian greene thank you for all the very interesting information over the years I personally think you are the smartest man alive today ❤
Awesome! Best start to my Saturday morning walk
Finally the shows continue again. Could we have an indepth episode around the possibility of black holes actually creating universe's within as the laws and the way it wouldcappear to work make sense minus a few human errors.
brilliant as always Brian
As a die hard fan, yes 😂 love to have you all back
Thanks a whole lot for all your efforts.
Dr. Brian Greene with a Dave Portnoy reference is pleasant but mind-blowing enough for the today, thank you.
So nice to meet you again in this beatiful green place from Your Daily Equations 💚 Thank you for another great session and best greetings from Poland👋
Without Dark Matter the galaxies would not be in place. It holds them together❤
I miss your videos Brian! ‘Equation of the day’ videos during the pandemic were my favorite
Oh shoot! I missed being here when you were live. So glad to see you doing these again!
Beautiful people. Beautiful ideas. JF lovely!
She is amazing . WuuuuUUUUPPP!
Heard when the black holes merged at LIGO also the neutron stars merged too🎉
Thank you, this was great!
I had a fun time joining the live
I plead the fifth
I love when guest speakers are as eloquent as brian green and dont say uhm or uh after every word as some do
Great show. I have Physics degree so understand the maths behind it. However, great to see this discussed in open forum for the general public, most people are interested in space stuff.
PS Good to see physicists that seem natural with a sense of humour
PPS The thought that we may soon detect gravitational waves from big bang ir superstrings thrills me
Vous êtes utile M. Greene 🎻
Very nice! Thank you.
Fabulous listening to you guys. I follow ESA on Facebook, if you don't, please do as you get all the info for and from the missions. I'm obsessed with dark matter and dark energy so bring it on Brian!
She is the best to explain LIGO, ... Gracias Gaby(14:00)
Dr. Greene bringing that "3rd funeral this week" energy for this episode. Lol. Still amazing as always.
Thank you! Appreciate your brilliant Narration surge of expansion etc.. Gives me a window of insight on your cosmology explorations with your telescopic lenses with its varied tech progress! To answer "Why"? ❤❤❤for sciences matters Thank you!😮
i love this scientist. chiara is eloquent!
Nice background looks very peaceful.
Great analogy on cosmic strings by Brian. I feel like I somehow understand
32:14 One of my puppies did that tonight, but he also snapped his leash. So, naturally, I'm wondering whether or not spacetime or its fields could snap from the tension on them? Would they form new loops of the string, vibrating at new relative frequencies and so as different particles?
We won't go quietly, the Legion can count on that.
In a corner of his house, Dr Brian Greene hosts the most coolest physics forum there is! I only have one question as the result of watching this gravitational discussion.. Is a black hole made of dark energy/matter?
You had me at “Frankie” 1:53
I Really like the idea of space being a partical
I miss those long Q&A Brian that you did during the pandemic
Feel a nostalgia for those days.
Can't wait to see the cosmic gravitational wave background in relation to the cosmic microwave background.
Wow. Thanks guys for discovering more about gravity. And now we have the ability to see the universe in the way a bat does.
Thank you, most interesting, I hope to travel to NYC in September.
An interesting subject for me would be how strings might be in the early universe & whether they have any tendency to clump (build into a quark).
The evolution of dark matter and matter looks so much like how our brain’s neural network forms does it not? Isn’t that remarkable? I just find it so beautifully ironic, almost as it is intended. Patterns like this are everywhere in nature. The universe is no exception. What a wonderful time to be able to discover these things … we are the pioneers for future generations.
We are in the brain of god ❤
... or the 'fruit' of the universe
great leacture
Roger Penrose suggested that in our universe there could be Gravitational Waves from Black holes coming from a previous universe in the very far past. If such a previous universe Existed and if Black hole morgens emitted gravitational waves: could these waves be measured with the Neutron Star method? Or would such waves Still be beyond our reach and not a Potential source?
As a layman in this area ...
I understand that two orbiting masses should spin arround each other forever ... but they loose velocity and collide and one way they loose that energy is by dispersing gravitational waves. Is this correct? If so it then implies that energy is required to change the state of gravity. It also implies that there's a direct similarity between electromagnetic waves and gravitational waves. It's just at a different scale.
It looks so bright and green behind you.
That justifying his name Green-e👍 I pronounce his name as Brain-Green😄 He is such a charismatic and enthusiastic scientist 🎉🎊
i like Brian Greene he cool
Great a woman!!! I started in Berlin with science in the Otto-Hahn Bau in Berlin, Germany! Lise Meitner!!!
And sincenI have been a teenager Marie Curie was my role Model!
Than came Heisenberg and others.
I studied Biology, than switched to medical research, cancer research and from 2001-2008 and Harvard, first Postdoc and than became even a faculty member at Harvard Medical school
Why only two arms for LIGO? Wouldn't a “3D mesh” of arms give us much better detail? Surely we could separate out the direction and magnitude of the waves with an array of detectors.
A solar system sized black hole.. orbiting another black hole the size of our solar system... That's some serious imagery. Even though we don't know why gravity is. I love you world science festival
The moment a particle is a wave; it has to be a conscious wave!
Gravity is the conscious attraction among waves to create the illusion of particles,
and our experience-able Universe.
Max Planck states: "Consciousness is fundamental and matter is derived from Consciousness".
Life is the Infinite Consciousness, experiencing the Infinite Possibilities, Infinitely.
We are "It", experiencing our infinite possibilities in our finite moment.
Our job is to make it interesting!
... or at the _very_ least we start looking/thinking in these other ways, or directions.
ive become more and more disappointed over the last 20...30 'odd years because of the unwillingness to even think in these... other ways.
admittedly its taken me most of that same time to open up to them,
I was very 'science only/has all the answers' based and unwilling to examine these "so called" fringes
but, if honest they are just other ideas /points of view and in many cases being thought of, or believed in for much longer.
i sometimes wonder if this build up of "dark matter /energy" (2 other words for... we don't know)
is the 'manifestation' of the enormous amount of information we have generated in the last few hundred years
painted onto higher dimensional 'shaped' objects that we can only see/interact with the equivalent of a shadow, or reflection of our 'every day' objects
a reflection/shadow of something having vast amounts of near massless, but seemingly correct information about the objects
but only when viewed in a very certain way
like slices of the 3d object does when viewing in flatland/lower dimensions...
I hope that makes some sense 😊
Is it possible that there is a space that is preexisting that our universe is expanding to fill, and what looks like a force pushing out and expanding the universe is actually a vacuum pulling out?
1:14:18 is that the 11 hour video now on TH-cam?
😒...Bruh! That thing is to loooong. Fr.
While I am sure there is plenty of room at he L2 point for the instruments parked there now and planned in the next few decades, is there any risk of cluttering it up? Or is the L2 point sufficiently orbitally unstable that instruments that fall into disuse will drift out of the region?
Welcome to the PTA meeting.
I've been posting this story for a while, now. Is it possible it's related to gravitational waves?
Time is fascinating. I worked the subway stations for nearly 10 years. From one end of the city to the other. Every so often I would notice the city would be saying that, "Today just flew by" or "The day was just dragging along." How can an entire city, with no interaction with each other until they used the subway, complain about the same time paradox unless it was effected by it? Maybe a time distorted bubble the earth passes through in its revolution around the sun. Maybe random waves of time distortion hitting the earth? Maybe they're given off by the sun. Maybe they're from outside our Terran system and reach us in intervals. ???? Ti-i-i-ime, is on my side. Yes, it is!
If you can think of a better way to do a blind survey of an entire city, in the small window of opportunity, I'm all in. Until then, I invite you to spend a couple years in the subways, during rush hour and you'll see for yourself. Just listen as an entire city gets off of work and gets out of school. You'll see it's more than a, "coincidence of circumstances."
that's an interesting observation
and as i understand it, yes,
like a boat riding the waves, a large wave (or smaller boat) has to ride it as a whole
up one side then down the other
Very eloquent presentation! Although i would be curious mister Greene to hear your real point of view on a foundation that it’s main goal is to blur the laypeople about a non existing relation between two incompatible identities…
Dr. Greene, if I could suggest a topic, it would be the origin of the Solar system and how similar or rather, different from exo solar systems it seems to be, thank you!
Hi Guys; what's the force carrier for the G wave and/or the medium transferring the wave energy across space? Please disregard the headlights and get out of the roadway.
I've always been curious about the structure of the universe, like if we could map out the universe in an I instance of time, mapping light years. What would that look like
please have a guest who did a double major in audio
In a tug of war game, both of team members are on the same ground (same plane). What about tug of war in our solar system? Are their orbits on the same plane or changing time to time?
yes, we are all 'playing' on the same 'ground' or space /time as its called.
or 'Substrate' is a word I like to use
@@2Worlds_and_InBetween Thank you. Good to know
@@vitr1916 👍
Lol , just think some day we may have gravitational wave radio. Songs like Yoi put the weight on me will be popular!
So gravitational waves are not effected by time dilation?
When two BHs are merged, time is slowed down relative to the earth. Like a movie "Interstellar", one hour on the planet next the BH was 7 years on the earth relatively. So say it took 2 seconds at the last moment of the merge and we here on Earth detected it. It's still the same 2 seconds? No time delation? Would that mean there's no "red-shift' because of the expansion of the universe, spacetime?
that 1st gravitational wave almost killed me...
I'm confused. Much of this discussion centers on the idea of demonstrating that gravitational waves exist - in the first place. But didn't Taylor and Hulse already demonstrate that in 1974 using pulsar timing measurements at Arecibo with sufficient credibility to win the Nobel Prize in 1993 ?
Is it a gravitational wave if the object first comes closer and then goes further away. I observe from afar, does the strength of gravity vary? A normal thing like the tide in the phenomenon?
Hi, you could just have a laser source in sphere with bilateral minimal blind spot and achieve the same thing on a smaller scale.
If dark energy were moving through the universe like heat through water, mass should be brought together like foam on the surface. That would require dark energy to move faster than light, maybe with continued influence from the cosmic origin on mass. Or for a strange geometry in time space
I still have no idea what cosmic strings are ^^ I wished he would have used more a mathematical description. Now, I am not sure if he talks about topology or geometry or fields or if it just was a nice image.
What is the vertical/diagonal band which crosses the galactic plane, which Euclid won't be scanning?
Is there a distance close enough to earth to where we would feel these gravitational waves but far enough away not to destroy the earth??? If you could hypothetically move the two blackholes.
@briangreene
In my view the phenomenon of gravitational waves indicates that space time is compressible. This indicates that space time has a variable density. I would expect that density to increase in the presence of baryonic matter so that a large amount of mass will bend the path of light in the same way that light passing through air and entering water is bent. I think that Einstein used the wrong terminology to describe this effect: mass does not curve space but rather compresses space. This may indicate that matter doesn’t exist within space but rather it displaces space. Therefore the larger a mass is the more dense the adjacent space will be.
Mr. Green is AOK on these videos ...
What is Black hole & how do you define it
🙃🙃Maybe the universe is not expanding maybe it is us and our measurements that are shrinking.