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Observing time

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Yesterday’s post, ‘Let’s Do the Time Warp Again’ is still messing with my head a bit. The idea of the Andromeda paradox suggests that if we are in motion compared to another bystander, our view of very distant events can be days apart.

I understood relativity with respect to travel, a twin in a spaceship travelling close to the speed of light goes to a distant galaxy. When he comes back to earth a few years later he would be younger than the twin left behind… demonstrating the relativity of time. But the idea that distant events can ‘happen’ at different times for people witnessing it from almost the same spot, simply because of their relative motion to each other is perplexing.

So then I suggested that we could re-witness an event by changing our motion such that we are moving quickly away from a very, very distant event, so that from that relative perspective the event hadn’t happened yet. I’m no physicist, the distances would have to be huge, and I don’t know what speeds would need to be achieved, but it seems pretty conceivable to me.

What’s messing with my head is that if this is possible, what does ‘now’ mean?

We have to wait 8 minutes for the sun’s light to reach us. When it reaches us, the sun is already 8 minutes older. We don’t see the sun now, we see its history. Our concept of now has a perpetual lag.

This then got me thinking about animals and their reaction times. Have you ever seen a video of a cat toying with a snake? A cat can avoid the bite of a snake, always reacting faster than we would be able to. How does a cat perceive ‘now’ differently than us?

How do birds fly in a murmuration? The flock changes direction in waves, so quickly that they can stay in formation despite hundreds of them having to coordinate with each other. How does a bird in a murmur perceive ‘now’ differently than us?

To a ten year old, 5 years is half a lifetime, to me it’s less than 1/11th of my life. Is it any wonder that as we get older, time seems to go by faster?

Like I said, these ideas are messing a bit with my head. They make me wonder what ‘now’ means and if in reality we share a ‘now’ with anyone? Is the mere act of observing ‘now’ just a relative glance of varying histories? And yet the only thing any of us ever experience beyond our memories and imagination… is now.

Let’s Do the Time Warp Again

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“It’s just a jump to the left… it’s a jump to the ri-ight🎵”

…And that’s all it takes to witness two completely different views of what ‘right now’ means:

“The Andromeda paradox, proposed by physicist Roger Penrose, is a thought experiment in relativity that highlights how simultaneity depends on an observer’s motion. It imagines two people walking past each other on Earth: one toward the Andromeda galaxy and one away. Because of special relativity, the plane of simultaneity for each observer tilts slightly, meaning that the events they consider “happening right now” in Andromeda could differ by entire days. This illustrates that what is considered the present in distant regions of space is relative to an observer’s motion.” (ChatGPT)

Here is my thought experiment based on the Andromeda paradox:

If we were to witness a supernova of a star hundreds of light years away, could we send a rocket hurling at a high speed away from that event and capture the event happening again? Could we re-witness the supernova, a past event that happened many years ago, but from farther away? Would it be possible that from that perspective the event has not been witnessed yet, and so we can ‘get ahead of it’ focus our cameras on it, and wait for it to happen again, just for the first time from that relative perspective?

My head hurts a bit trying to make sense of this, but my hunch is that it would be possible. So instead of the Andromeda paradox, it’s more like the Andromeda mirror, bouncing back the same light but at a slightly later time than the present… which already is what a mirror does. 

Inconceivably vast

Webb’s First Deep Field is the first operational image taken by the James Webb Space Telescope. The deep-field photograph, which covers a tiny area of sky visible from the Southern Hemisphere, is centered on SMACS 0723, a galaxy cluster in the constellation of Volans. Thousands of galaxies are visible in the image, some as old as 13 billion years.The image is the highest-resolution image of the early universe ever taken. Captured by the telescope’s Near-Infrared Camera (NIRCam), the image was revealed to the public by NASA on 11 July 2022. (Wikipedia)

It’s too hard to fathom just how big the universe is. The image below only shows a few stars, they are the bright spots with 6 flares coming off of them… a by-product of the James Webb telescope’s design. The rest of the bright spots are galaxies. Galaxies that each hold billions or trillions of stars.

And if you held your pinky up to the night sky you would completely cover the area of the sky that this photo covers with a sliver of a finger nail.

We are so insignificantly tiny, and our Milky Way galaxy is so insignificantly placed in the universe. We just can’t conceive of just how inconceivably vast our universe is, and how insignificantly tiny our solar system is.

It’s too much to comprehend. And yet, here we are. So significant to each other, so connected to our planet. We get to live lives rich in mystery and wonder.

What other life is out there, or was out there, some time in the 13 billion years of our universe’s existence? Could alien life comprehend our existence? We’ll probably never know.

If there was life in one of these distant galaxies right now, we wouldn’t it know for millions or billions of years. The light we see in that photo above are from the past. To put it into perspective, if they were looking at light from our planet, they would be seeing light emitted from before dinosaurs roamed the earth… in other words they would be looking at prehistoric life on a planet with single cell organisms or perhaps no life at all… yet.

It’s too hard to grasp. It’s inconceivable.

Looking back in time

It’s hard to grasp the idea that when we look at a star, we are looking at that star from an era long ago. Even when we look at our own sun, we only see it as it was 8 minutes ago, because that’s how long the light takes to get to us. The closest star to us is Proxima Centauri at 4.25 light years away. When we see the light from this star we are seeing it as it shone 4.25 years ago.

When we look at the night sky, we are looking at a history of the universe, with each distant star sharing a different part of its past with us.

We look at people who are close to us in the same way. We don’t just see them, we see our past with them. We see the last time we met. Did we get along or did we have a conflict? Did we create a fond memory or did we face a problem? Did we grow closer together or does the distance from our last meeting make us feel farther apart?

In a way, relationships can be like distant stars, fading into the past unless we make an effort to see people in a new light. Because our connection to people comes from the way we look at our previous interactions, our history together. This is all we have until we shed new light on one another. Glimpses of history that tell stories… be they stories of our universe or stories of friendship. In both cases we are looking at our past to make sense of our future.