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| Step two: Mushrooms |
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| Carrots potatoes and wine/chicken stock |
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| Fours hours later, dinner is served! |
Recently I just read a whole bunch of relatively shabby explanations from students of why rotating spaceships can simulate gravity. These are seniors who have taken a full year of physics and are currently in my astronomy class so they are well equipped to give a decent explainer, but most of them just said something like "centripetal centrifugal, blah blah blah". As I was looking over their work, I realized that one of the major conceptual problems is that a true understanding of why this works involves a tale of two fake forces:
Fake force #1:
Gravity
You don't actually ever feel the force of gravity pulling you down into the ground (contrary to what I teach my student to draw on free body diagrams!). Rather, you only feel the normal force pushing up on you (the opposite direction!). This was one of Einstein's key insights in revealing the General Theory of Relativity. Since gravity is really just an alteration of your inertial path ("warping of spacetime"), it is not a force. What you feel is the ground pushing up against your inertial path so you assume something is pulling down on you.
Fake force #2:
You don't actually ever feel a force pulling you out of a circle (or a turn). Rather you feel a force directed towards the center of the arc of the circle of the turn you are making (the opposite direction!). The force is required to keep you from following your inertial path (which is tangent to the circle). Since you feel the force pushing inwards on you against your inertial path, you assume something is pulling outward on you.
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So, "artificial gravity" on space stations (accomplished by walking on the inside of the outer surface of rotation) is really the swapping of one fake force for another. Either way, what you feel is a force on your feet preventing your from following your inertial path (the one you would take without any forces).
According to Einstein, we've been experiencing gravity as an upward acceleration on our feet our entire lives. So, if you stand on the inside of a rotating surface, a 9.8 m/s/s centripetal acceleration to keep you going in a circle will substitute quite nicely for a gravitational field of 9.8 N/kg. In one case we are accelerating inward to curve through space and in the other we are accelerating upward to curve through time.
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| The movie we were discussing was "Interstellar" |
"If a person falls freely, he will not feel his own weight" - Einstein's 'happiest thought'
‘Round, Round we go -
Another year over
And a new one just begun;
A time of renewal,
Yet another bite at the apple!
We cycle our personal calendars from December back to January,
Feeling younger and refreshed.
The Earth rotates, carries us out of its shadow -
Not just the dawn of a new day but a new year:
The Earth revolves anew around the Sun.
Circles nested within circles.
How deep does it go?
Arbitrarily, we mark the passage of time:
Reflect,
Take stock,
Look forward and celebrate the renewing of the renewal
Which we pretend will never end.
‘Tis not a true renewing though,
As it is predicated on the old;
The new year has the old one embedded within it.
I will not be getting any younger.
The planet will not sweep out an identical
Path through space and time.
The Sun is lighter, our ellipse precessed, space expanded and cooled:
Nothing is exactly the same
Our personal and Universal entropy climbs
No matter how we mark the time.
Nonetheless, we celebrate the completion of a lap.
The idea of renewal,
Marking the moment,
They are not valid but they are necessary.
Invalid validness keeps me going on,
Keeps me spinning round,
The cognitive up and at ‘em my small brain needs…
So, three cheers for another lap, world of mine.
The changes are slow enough and my vision poor enough
I can tell myself all is possible once again.
We are all riding the tide of entropy
Sometime between too low (boringly ordered)
And too high (boring in its disorder).
Like a catapulted sleeper
Who awaken near the apex of his flight,
Enjoying the heights of the ride
Having missed the ascent
And falling asleep before the descent.
What a glorious time to be alive,
What a view our big brains have earned
Examining those Keplerian ellipses we ride.
The clockwork of finite nested circles that is the universe
Spins not forever -
It had a beginning and will someday end,
But what glorious turning for now!
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| AI art generated from lines of this poem |
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| Tomato and Spinach Pastas! |
I was reading a New York Times article about the "Last Beatles' Song" and pondering this new reality we find ourselves in, fretting over Deep Fakes and authenticity. I share the unease that most do, but what I am understanding today is that we are just entering a new reality where, in the future, it will seem quaint and (perhaps) cool for live people to perform in front of cameras and create movies the traditional way. My first experience of this was was in the Star Wars Rogue One in which both Princess Leia and General Tarkin appear but there is no actor/actress alive to do that role anymore.
So my prediction is that AI enhanced Deep Fakes will not replace music and cinema as we know it, but it will become the de facto production method in the future (or at the very least, a prominent element in the product). We will, however, still honor and enjoy the quaintness of non-enhanced music/movies and, even more so, the occasional in-person live event.
Unavoidably, future novels, music, and movies will all have AI written/enhanced elements to them unless it is marketed as an "organic" product as a novelty. Perhaps future generations will look at this decade as comparable to the invention of the printing press or the record player. The change in paradigm was not overnight but the societal impact was deep and profound. Fear of the printing press was real and similar to fear of this AI revolution, but I'm guessing we will settle into a new normal and be just fine with it...
So even though I am slightly put off with dead actors and musicians putting out 'new' work, I'm thinking I need to get over it. I'll try to acclimate by enhancing this 'organically' written post with some AI generated art:
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| AI generated from the prompt "Fear of an AI future" |
On the other hand, Nick Cave says we should fight AI tooth and nail:
My brother just now mentioned that he was waiting on his visa for his upcoming trip to India and I said "Oh, I know all about that!" I looked for the blog entry here that details that fiasco but it turns out, I never blogged it! Here we go...
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As I have blogged before, in the mid-to-late 90s I worked for a company that flew me around the world doing some technical work for them. One very memorable trip for me was to India.
Before I left on that trip, I found out I would need a visa to travel to India. Back then, formalities like this were just part of the landscape of life ("I'll grab lunch over there, swing by the Indian Consulate, and come back to work around 2PM); now I feel like I have to shut down an entire day to get something bureaucratic like that done. In any case, the guy helping me with the visa pointed out that my passport expired later that year. I was like "So?" and he kindly explained that India does not let people in on a visa on a passport that expires in less than 3 months. I was kind of incredulous as I had return tickets for one week after my arrival. He shrugged and gave me my visa and I went on my way.
Fast forward to my actual trip: After a hop from Houston to Los Angeles, I tried to check in for my flight to India and the lady wouldn't let me. The reason: my passport was expiring too soon! What? You mean the guy whose job it is to give out visas knew what he was talking about? Who would've guessed?
So, I talked with the check-in lady and she put me on the list for the last flight out that night (this was an early flight) and I went off to find the State department offices and beg for a new passport. After a 15 minute taxi ride, I went in and pled my case. Luckily I landed in the hand of sympathetic young guy and he rushed it through and issued me a new passport within a few hours. I didn't even know that was possible! To keep the visa, he punched a hole in my old passport and I carried both with me and had no further issues. Honestly, I'm kind of amazed it all worked out. Back then, I didn't know any better so I tried to make it work out and... it did!
Oddly, the taxi ride back to the airport was taking over 30 minutes and didn't seem to be traveling the same efficient path my earlier ride had taken. I sighed loudly and, all of a sudden, the driver hopped on to an interstate and I was at the airport in less than 5 mins. Strange how that happens, huh? Only time in all my travels around the world where I felt like I was literally 'taken for a ride' by a taxi was here in the USA!
Note to self: Don't try to out-think bureaucracy, just comply.
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| AI art prompt: travel red tape passport India |
So, I wasn't a very good grad student. My grades were okay, but I was a bit directionless. On my way to my Master's degree in Physics (which was just supposed to be a waypoint on the way to the PhD but well, you know... stuff happens), I was mostly taking classes. The thing is, I thought I would understand things better. It turns out that the old adage "the more you know, the more you know what you don't know", turned out to be very true in my case. I always felt like I was on the verge of learning/understanding something very cool about physics... but never quite arriving.
There is one glory moment that I like to relive though. It was in Statistical Mechanics. I was really looking forward to this class and it was taught by a relatively charismatic faculty member who was about to become the department head of the physics department. Turns out, he wasn't a very good teacher (if I had a nickel...). He would assume we already knew stuff we didn't know and spend lots of time on something obscure that he found interesting and then he would give us tests that were only tangentially related to what we have been doing in class. It wasn't just me, all of the students in that class were a bit frustrated with that experience. (To his credit, after the class, he came by and asked several of us to tell him why it went so poorly so he could do better in the future!).
Since I wanted to understand what was going on, I picked up an old textbook of my father's (I just googled and found that it is still exists, but I'm pretty sure Amazon is making up this edition number!)
