Recent content by syfry

Context from history adds a vital perspective and makes science come alive. Students study the history of models and theory, right? Einstein had updated an equation in his original paper after publishing it, nearer to the eclipse, and good thing for his adjustment had brought observation of...

Out of curiosity, 1.2 messages posted in which area... in the lounge under the exciting sub forum of feedback and announcements? We can go the science route and test the hypothesis: open a main sub for science history, and see what happens instead of relying on our assumptions. Plenty of...

Your words could resemble an apology if you work on your phrasing and sincerity more. Inspired by #13.

Forgot to ask, does this part from Wikipedia mean that the stars do move at a 26,000 year pace, and did ancient astronomers notice? " ..because the equinoxes moved westward along the ecliptic relative to the fixed stars" (if you or anyone happen to know) It's why I asked in the previous...

Thanks for pointing that out. 👊 Does that mean they did or didn't notice the stars move? (with such slow changes from the 26,000 year cycle of axial precession) For me personally, and possibly for many more people than you might suspect, my reading comprehension plummets for technically worded...

Citation please. Thanks for replying. 👍 I had problems finding out how they tracked that stars had slightly moved from their position. The rest of your comment sounds like assumptions.

An article in Britannica and another in Wikipedia had led me to the conclusion. From Wikipedia: "Earth's precession was historically called the precession of the equinoxes, because the equinoxes moved westward along the ecliptic relative to the fixed stars, opposite to the yearly motion of...

They might've used water clocks under candlelight to track time by dripping to marked levels of water. They might've used star dials (like sun dials but in the dark). They might've stuck objects into the ground that stick up and align with stars so they'd notice changes in position. But I didn't...

Now seeing the big flaw in my scenario. It's apparent by visualizing lower speeds on a globe, no math needed. If the x we're traveling is south to north in a straight line along a longitude line, it's impossible to then accelerate into y along the equator or along any latitude line. We'd be...

I had assumed they never added over the amount of c because of how our slower travel through time will prevent us from gaining on light no matter how fast we travel. So I had mistakenly thought we'd perceive our 3 perpendicular speeds each at 99% c but the total couldn't break 100% and light...

"In other words, you can't just wave your hands and say that boosting by 0.99c in a given direction will always add a component of 0.99c in that direction to your velocity. You have to actually do the math." Who wrote those words? Your phrasing is 'by 0.99 c' while mine is 'until'. Did you...

Surely if the physics used only math and no words, it'd be almost useless. If traveling by car and I boost by 100 km per hour, then it's 100 + current speed. If I boost until 100 km per hour, then it's only 100 total. With relativity, that might mean a boost by 0.99 c could fall short of...

Ok, so I get it now. 👍 And to be clear, since the wording feels unclear... is 'boosting by 0.99 c' the same as 'boosting until 0.99 c'? Are those identical statements?

If it's post #15, then it's cool you're trying to teach me that accelerating into a perpendicular direction would end up at a lower speed than if accelerating into the same direction: "If I accelerate for 1s at 1g I end up doing 10m/s. If I accelerate for 1s at 1g again I could be doing 20m/s...

Right, feel a reminder was needed due to the detours about what I actually asked.