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20 March 2018

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Welcoming P to the page. P, please meet my friend HL. HL, I just met P. Guess what? That’s what happens, here in S P A C E. Conversations, continuations. I have been on a bit of a roll, lately. Probably has something to do with being in the West for a time again. In the West I have my bearings better; I’m ‘of’ that kind of culture where you go out and do stuff and be brazen about it and who cares about it all. The exact attitude that has gotten us into this weird downward spiral (to be pessimistic, as I think I was, at the time we had met?) / this time of reflection and awareness that something’s gotta give (more optimistic attitude, brought about in some part by my newish friends who are talking about this U Lab class at MIT about how everyone needs to be more empathetic if we’re to solve the world’s problems, etc, or something, I’m not an expert (or doing the course) so it’s all secondhand and all that. As usual, I gather my data from anecdotes. Ha.

You? How are you? How is the writing going there?

To reply to Cameron’s question, yes, I’m a physicist (or at least hoping to be – I’m currently working towards my PhD in theoretical physics) and a science enthusiast. My current research topic is part of a burgeoning field that builds on the pioneering work of Stephen Hawking on black holes, and the unification of Quantum Mechanics and General Relativity. In a nut-shell, I’m working in a sub-topic of String Theory that focuses on solving for the right spacetime geometry of our universe. This is a nod to what I’ve said before about the Einstein Field Equations above and how spacetimes in general are solutions of these equations.

This is why Stephen Hawking mattered so much to me. He was the Albert Einstein of my generation. His results on black hole evaporation (a.k.a. Hawking radiation) literally opened a new field of research that is extremely active today and that is at the confluence of Quantum Information and Quantum Gravity. I guess this answers partly Dipika’s question about the influence of Stephen Hawking on me (as someone who is training to be a physicist). To us, physicists and physics students, our heroes are path-breakers in the fields – People who establish fundamental truths about the nature of the universe and reality. We all have very finite lives to live, and in every few generations or so, there is someone brilliant who comes along and points out some small (but astounding) aspect of the vast reality that we’ve all ignored. For me, it is an immense privilege to be alive in this exciting time when such discoveries were made and put to good use (To be alive during Einstein’s time would have been wonderful too – I guess).

Anyway, if you have books or articles about science-related matter (like A Brief History of Time, or articles on Quantum Computers or whatever that catches your attention), I hope that you’ll get to them at some point – I’m not trying to sound biased or anything – but time spent understanding science is the best kind of time spent to me.

Cool! My best wishes for success in your studies, HL!

I will be sure to let you know when I do get to the articles! A Brief History of Time has been on my long-term list as well.

HL, would you care to read some of the conversations that are starting to gel in “New Geometries?” It’s a different page, and post. Most welcome, and if you like, I’ll send a link and password.

Thank you for the very nice transmission from 20804d ! I also got your other messages about the orientation 🙂 The other day I was just looking up different geological time scales in the history of the Earth and apparently, we’re in the Cenozoic Era (the Age of Mammals). I have read about this long ago but have forgotten all about it until recently when I was suddenly reminded of the fact that the life span of a species is finite. We as a human species has only been walking the Earth for about 190,000 years. The dinosaurs walked the Earth for 181 million years before their extinction (they lived from 247 million to 66 million years ago). 181 million years – Imagine a species that lasts that long and that actually develops a civilization ! What technological advances would that civilization be able to attain? Even our wildest science fiction writers would not be imaginative enough to write about a story that is 180 million years in the future, if the human species can last that long. I’m not sure if we’re as resilient as the dinosaurs. When they got started in the late Triassic Period of the Mesozoic Era, the (single) supercontinent Pangaea was still in place (Of course there was no Africa, Europe, Asia, North/South America, or Australia). The dinosaurs survived the breaking up of Pangaea into Laurasia and Gondwana at the end of the late Triassic and grew during the Jurassic to become the dominant life form on our planet. They even survived the further breaking up of Laurasia and Gondwana into the continents we know today during the Cretaceous period. So they literally survived two “ends of the world” and kept evolving until finally taken out by an asteroid. I guess my point is, in the big picture, we’re just a chapter (a very short one so far) in the geologic history of the Earth. Whether we’re still around in 180 million years depends crucially on what kinds of fundamental scientific breakthroughs and technological advances we’re able to make. Among many, many other things, we probably need the kinds that help us evade an asteroid, if/when one comes hurtling at us.

HL, I just updated the password to this page. It’s ‘abillionsuns.’ I went to the planetarium in KL and got to see a movie with the title, ‘Journey to a Billion Suns.’ Was. So. Great. I’m processing my feelings around it and wanted to write to you here when I do find my way to something short, coherent. Would that be okay?

Also going to invite a new friend, PH, to join us in this thread… P, welcome, if you see this! Welcome and let me introduce you to my very intriguing friend, HL.

Who is also very busy through the end of the year, so we can keep this space as a placeholder for intermediate banter, if we like, between now and then.

Thanks and more soon!

D

HL, Cameron–

Hey. Cameron, if you are getting these notifications, ‘hi!’ from S P A C E. Sorry I had to change the password here to keep up with the current memberships, but yeah. There’s somethign I wanted to ask HL–related to this thread.

HL,

Um. Multiverses and multiple dimensions: what is the relationship, there? I want to try to wrap my head around this, but I guess, in some ways, it’s out of scope. Still, I’m exploring things with others now in conversations here in other spaces, about philosophy x physics, in both instances, contemporary. So yeah. Bringing the new physics into the space of new philosophy, which has been dead for too long because it’s been out of touch with people who are really thinking, really investigating, really asking questions, and sort of also been overwhelmed by dead white guys and what they said before Planck found ‘h’.

Time to get updated.

I want to move the ball now, in that momentum.

What should I be reading? Who should I e-meet? What should I do?

Do you want to be on my podcast, also? I can interview you online through Zoom. I’d love that. (See http://soundcloud.com/designkompany). Getting going now. Getting going faster and faster… increasing speeds, accelerating like 9.8 m/s^2 and then some.

To the next!

DK

Stephen Hawking was a giant, giant intellect – the same league of intellects as Isaac Newton who invented calculus (yes, the mathematical calculus that is so prevalent today), and Albert Einstein, who discovered Special and General Relativity. He was a general relativist – a theoretical (high energy) physicist working in field of General Relativity (GR). In the physics community, Hawking was (inarguably) the most powerful authority in the subject of black hole, and more specifically, he was the very first physicist to understand the quantum nature of black hole. This was a huge step for science – His 1974 scientific paper on the evaporation of black hole was an astronomical step towards a quantum theory of gravity. At this point, all this is just words – hardly meaningful to a non-physicist, I guess. To explain all of it would make the post too lengthy. I’ll just sketch the big picture.

1. There are many kinds of spacetimes. Meaningful ones are solutions of the Einstein Field Equations (EFE) – the product of the theory of General Relativity (GR). Our nearly flat spacetime is definitely one of these solutions. Cosmology is an off-shoot of GR – a sub-discipline studying cosmological solutions of the EFE.

2. Black hole spacetimes are solutions of the EFE as well – They describe extreme kinds of spacetimes: Those with event horizons and singularities hidden behind these event horizons. The first black hole spacetime solution was found in 1915 by Karl Schwarzschild, a German physicist/soldier who died on the battlefield of WWI. More black hole spacetime solutions were found in the 1920s and 1930s up till now. For a long time, it was thought that these objects were purely theoretical – After all, they couldn’t be real since they were thought to be so extreme. Nowadays, almost all trained scientists accept their existence unquestioningly, since a vast amount of observational evidence supports their existence. In fact they’re so ubiquitous that every galaxy in the universe should have one right at the center.

3. Their ubiquitousness doesn’t mean that they are not bizarre, exotic, and the most curious object in the universe. They’re actual holes in spacetime since their interior technically doesn’t belong to spacetime anymore. Astrophysically, they’re formed by supermassive stars that have run out of fuel for nuclear fusion to occur in their core and they collapse under their own gravity, forming a black hole. So what happens after a black hole is formed? The region occupied by the black hole is forever hidden and is inaccessible to all observers in the normal spacetime. Stuffs that get too close to the black hole get pulled into it by its immense gravitational field. The point of no return for matter to be pulled in lies at the event horizon itself. To cross the point of no return means to be doomed for eternity (if that exists). Inside the event horizon, no one knows what happens – The theory of GR breaks down and gives us no predictions except for 2 things:
a. There is a singularity that lies in the future.
b. Time and space exchanges role inside the event horizon. The only way forward for a timelike object leads to the singularity.

4. To understand the nature of black holes further, we need a quantum theory of gravity. There is no “the” quantum theory of gravity at this moment. Quantum mechanics and GR seem to be fundamentally incompatible, and the successful combination of these two discipline is the Holy Grail of modern theoretical physics. Without a quantum theory of gravity, we do not know what happens inside a black hole or at the beginning of spacetime (the Big Bang). String theory is an approach to a quantum theory of gravity, and is the most successful approach at the moment.

6. So, classically, these are the beliefs regarding black holes: They were thought to be eternal once they were formed – meaning that stuffs keep getting in and getting lost from our universe, the black hole itself would get bigger and bigger. All black holes were the same once they were formed, meaning that a black hole made of matter and one made of anti-matter would be identical to us (external observers), since we couldn’t tell what was behind the event horizon. In other words, black holes are forever black. Not even light could escape their powerful gravity. Here comes Stephen Hawking’s ingenuity in debunking these deep-seated beliefs and forever altered our notion of these monstrously bizarre objects.

5. Stephen Hawking was, like I mentioned previously, the world’s leading expert on classical black holes. Together with mathematician Roger Penrose, he derived many fundamental theorems concerning the (classical) nature of black holes. Again, he was a general relativist. However, he was the first physicist to put quantum mechanics and GR together (in a certain approximation that doesn’t require gravity to be quantized, but matter has to be quantized) to derive the following striking results:
a. Black holes are not forever black. In fact, they evaporate. The radiation leaking out of them are purely thermal in nature and bears the name “Hawking radiation”.
b. Information regarding the nature of black holes might not be forever lost.
The second result is an active (feverishly so) area of research now. So, in fact, Hawking presented us with a glimpse of black holes that was never possible before – He took GR and QM to a level tantalizingly close to a possible union to reveal the darkest secret of the cosmos: the quantum mechanical nature of black holes. In the 400 plus year history of relatively modern science, very few people have managed this feat before (possibly fewer than 10).

So there you go, the legacy of Stephen Hawking, in a few sketchy paragraphs.

HL,

Thanks for all of your descriptions of the underpinnings of the work of the amazing Stephen Hawking; they’ve made for interesting reads, on top of that romanticized movie about him from a few years ago. Are your a physicist? Or an physics enthusiast?

I’ve read about bits of quantum theory at different times, including a few books, plus a class in college called “The Origin and Evolution of the Universe” (just as awesome as it sounds!) I was often taking fun classes like that. Oh yeah, and one called “Shamans, Epic Poets, and Musicians in Central Eurasia” (according to your definition, a bit outside of the realm of science, perhaps! Made for a good final paper on “Weather Shamanism” however! Lots of fun. Oh, and I even took one class that oriented me to some issues affecting the area of the world in which Dipika now resides. “Political and Social Economy and Ecology of Natural Resources in Southeast Asia” (focusing on the Mekong river). The elective course authors didn’t seem to believe in short, to-the-point course names, did they?

Another somewhat related thought: I somehow got on a Quantum Computing e-mailing list at Microsoft, my employer. People (employees) from across the global send interesting articles to the mailing list, and I haven’t bothered to create a filter for this mailing list–it’s not that high volume, and plus it’s interesting or at least could be–I have filed away some of the more interesting-sounding articles but have not taken the time to read them just yet. Soon!

Time and space are observer-dependent. There is no absolute frame of reference in the universe. It’s all relative – Hence the names Special Relativity and General Relativity for these two theories discovered by Albert Einstein in 1905 and 1915, respectively. When physicists say “space and time are the same entity”, it’s not literally the same thing not for a single observer or a singled-out frame of reference. From here on, observer and frame of reference are used interchangeably. It’s the same thing in this sense:

In Special Relativity, spacetime is flat and populated locally by the light-cone structure. Every particle or observer/frame of reference has a world-line that lie within their respective light-cone. A light-cone can be visualized on a 2D surface as a pair of upwards-pointing and downwards-pointing cones joined at their tip with an opening angle of 45 degrees. Because of the light-cone structure in spacetime, there are 3 kinds of trajectories/distances:
1. Timelike trajectories lie entirely within the light-cone
2. Lightlike (null) trajectories lie on the light-cone
3. Spacelike trajectories lie outside the light-cone and are acausal.
A stationary observer (A) whose trajectory in spacetime is purely time-like experiences a specific time and space (his/her own time and space being separate entities, not the same); but another observer who is moving very fast will experience another frame of reference with his/her own time and space. Again, for this moving observer (B), his/her time and space are separate entities, but B’s time is a mixture of A’s time and space , and B’s space is also a mixture of A’s time and space, and vice versa. This is what is meant by time and space are the same thing. Either time or space on their own
loses their meaning because their meaning is not absolute. My time is a mixture of your time and space and your space is a mixture of my time and space if we’re moving very fast relative to each other.

Think of the well-known twin’s paradox: Identical twins grew up on Earth – When they turned 20, one stayed behind on Earth while one got on a rocket blasting to Alpha Centauri. 60 Earth years passed – the Earth twin turned 80 and had aged 60 years when Rocket twin came back from his round trip to AC, having aged only 20 years. Rocket twin was now half the age of his twin brother. Here’s a striking fact: While the Earth twin stayed stationary on Earth, his worldline trajectory is maximally extended along the time direction while the Rocket twin’s worldline trajectory is shared between the time and the space directions – Time passed slower for him because he had been busy moving along the space’s directions. Think of space as being a horizontal axis while time is the vertical axis. Earth twin’s trajectory is purely vertical while Rocket twin’s trajectory is shared between time and space.

The faster you go, the slower time passes.

This is because of the empirical fact that the absolute (absolutely absolute) speed of causality in the universe is the speed of light and so space and time has to bend in different frames of reference to make sure that this speed stays constant. What does it mean? It means that for an observer A standing still on Earth – He’s not technically standing still – He’s moving through time at the speed of light. Observer B traveling at a significant fraction of the speed of light is moving not only through time, but through space as well, and since her speed must stay constant at the speed of light, time slows down for her. This is a repeat of the twin paradox above. The fact that the speed of light is absolute means that time and space lose their individual meaning. It is an empirical fact that the speed of light never changes – in any frame of reference – this is why we know time and space can only be understood as a single entity and not separate entities.

I guess at this point there’re many things to digest so I won’t mention Hawking and his many great discoveries – That topic on its own is enough to fill pages and pages of analysis. Just want to conclude by saying that scientists nowadays neither understand mind nor matter at the fundamental level, and consciousness is another deep issue that we don’t understand altogether so to equate mind/matter/consciousness would not be a scientific thing at all. This equation belongs at best to the realm of pseudo-science and I won’t go into that direction because pseudo-science is not science in the sense that it is not falsifiable. The hallmark of a scientific theory is the fact that it is falsifiable (can be proven wrong). If something cannot be proven wrong, it has no place in science.

This was neat to read. I remember we talked about this in person. Thanks for sharing!

I’ll need to go to the library soon and look at Hawking’s work again, though I found ABHT to be hard to sink into. Narratives help us find meaning; I suppose this is why I love reading, and also, asking questions.

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