The sun you see right now exploded 7 minutes ago and you'd have no way of knowing. You'd still feel its warmth. Still see it in the sky. Still orbit it. For 8 minutes and 20 seconds, you'd live in a universe that no longer has a sun and have absolutely no way to detect the difference.
This is because gravity also travels at the speed of light. If the sun vanished, Earth would continue orbiting the empty space where it used to be for the same 8 minutes and 20 seconds. Einstein proved this. The gravitational wave carrying the information "the sun is gone" propagates at exactly c. Light, gravity, and information all share the same speed limit.
Now scale the paradox in this post. 90 light-years is nothing. The Andromeda galaxy is 2.5 million light-years away. Every photograph of it is a 2.5 million year old snapshot. The entire galaxy could have collided with something catastrophic 2 million years ago. We'll find out 500,000 years from now.
The James Webb Space Telescope routinely photographs galaxies from 13.4 billion years ago. Those galaxies no longer exist in any form we'd recognize. The stars burned out. The civilizations, if any, rose and fell billions of years before Earth formed. Webb is photographing ghosts.
The deepest implication: "right now" is a local phenomenon. It exists only in the space you can physically touch. Beyond that, everything you see, measure, or interact with is a time-delayed recording. The further you look, the older the recording gets. There is no method, even in principle, to know the current state of anything beyond your immediate surroundings.
The entire observable universe is a 13.8 billion year old museum where every exhibit is labeled with a different date and nothing is current.
your body runs on an internal clock (circadian rhythm) meaning your body has a 24 hr biological clock controlled by the brain (the hypothalamus)... it controls body temperature, hormones, immune system activity, hunger, mood and even alertness
so at night , this system switches into recovery + low alert mode and that changes how everything feels.
why sickness feels worse at night is because of lower cortisol at night, cortisol is a hormone that reduces inflammation and pain. high in the morning and very low at night
so at night, pain feels stronger, fever feels worse, coughing increases, asthma attacks are more common... the sickness isn’t worse, the body’s anti-inflammatory system is weaker.
there are also several reasons why many deaths happen at night; the body is in maintenance mode, heart rate slows, blood pressure drops and brain alertness drops... so if someone is very sick, the body has less reserve power to fight failure
why you feel more hungry at midnight or at night is because leptin (fullness hormone) drops, ghrelin (hunger hormone) rises, blood sugar tends to dip, brain craves fast energy (sugar/carbs)... also your brain is tired, so willpower is weaker and cravings feel stronger.
the raeson why depression and dark thoughts hit at night, this is BIG... at night there is no noise, no tasks, no social interaction so your mind turns inward and ruminates.
brain chemistry changes, serotonin drops at night, melatonin rises (makes you sleepy but emotionally sensitive), dopamine (motivation) is lower... the brain becomes more reflective, emotional and vulnerable.
there’s also an evolutionary reason that humans evolved to be alert to danger at night, so the brain naturally scans for threats and negative possibilities.
why everything feels more intense at night (general effect) at night: less sensory input > brain amplifies internal sensations, body is tired > pain and emotions feel stronger, logical thinking decreases > emotional thinking increases... this is why breakups feel worse at night, anxiety spikes at night, memories hit harder at night, overthinking peaks at night
there’s also a psychological illusion, when it’s quiet and dark, your brain has nothing external to focus on, so pain feels louder, hunger feels louder, thoughts feel louder, loneliness feels louder... the night acts like an emotional amplifier.
a fun fact, crazy but true, doctors and psychologists say: never make big life decisions at night because your brain is chemically more pessimistic and emotionally biased after dark
learn something. 👍
Locals in Taiwan are trying to climb Taipei 101 after American climber Alex Honnold successfully reached the top.
The highest a local made it was about 10 feet up the 1,667-foot-tall tower.
The Taipei 101 tower is the eleventh-tallest building in the world. From 2004 to 2010, it was the world's tallest building.
After leaving Formula One racing, HONDA, released a lot of technical papers about their F1 powerplant in 2009. Which is almost unprecedented (although other teams like Toyota have done the same after quitting the sport).
Seventy years earlier, in the Second World War, such studies were also made, but instead of a computer to make the calculations digitally, glass engine parts were made, and using a stroboscope, fine aluminium particles were introduced into the flow, so that they could be visualised.
These were then filmed by high speed camera.
Nothing much changes in engineering really, it just gets easier to do.
This is why it is so dangerous as an engineer to take the easy way, without understanding and appreciation of the hard way.
Not all rosy-eyed views of the past are true, but believe, me, engineers of the past simply HAD to have an immense toolset of fundamental understanding and mathematical prowess to do the job at all.
As I said to @MrJamesMay last year at @WeHaveWaysPod festival, in 1930, in a top level engineering office provided with no internet connection, a pencil, and a ruler, I would be lucky to be the tea-boy.
But take an engineer from 1930, fluent in deep mathematics, they would take to programming a computer like a duck to water.
Old isnt always "retrograde" and new isnt always wholly better in every respect.
Using your knowledge to bridge the immense fundamental understanding of the past, to mate it to the almost unlimited computing power available today is the only way to suceed to a really high level consistently as a mechanical engineer today.
"sharing your plans prematurely triggers a "social reality" in your brain it gives you a fake dopamine hit of success before you've even started."
I'm starting to come around to this theory having a lot of merit.
1. Our skeletons are wet.
2. your nose is ALWAYS in your line of sight, but your brain ignores it
3. When you receive a donated kidney, they don’t take out the bad one. They just add the good one in.
4. Your immune system doesn't know you have eyes. Otherwise, it would attack them and make you blind. injuring one eye can introduce eye bits to the bloodstream and basically give your immune system the knowledge of having eyes. then it might decide it really fucking hates that and attack your non-injured eye.
5. The quality of the male sperm is responsible for morning sickness, preeclampsia, baby’s gender and almost every single pregnancy related issue.
6. You breathe through one nostril at a time. Don’t believe me? Put your finger below your nose and try.
7. The brain itself has no nerve endings, so it can’t feel pain. That’s why patients can be wide awake during brain surgery and made to perform certain actions.
8. That ringing in silence isn’t silence
When everything is quiet and you hear a faint ringing?
That’s your brain listening to its own nervous system.
You are hearing yourself functioning.
9. You will never experience your own death.
You only experience approaching it… Then nothing.
Everyone else gets closure, stories, funerals, and memories.
You don’t.
You never know you’ve become a memory.
From your perspective, the story just stops mid-sentence.