This Is Why Time Has To Be A Dimension

This Is Why Time Has To Be A Dimension

“But even two different objects with the same exact three-dimensional spatial coordinates might not overlap. The reason is easy to understand if you start thinking about the chair you’re sitting in right now. It can definitely have its location accurately described by those three spatial coordinates familiar to us: x, y, and z. This chair, however, is occupied by you right now, at this exact moment in time, as opposed to yesterday, an hour ago, next week, or ten years from now.

In order to completely describe an event in spacetime, you need to know more than just where it occurs, but also when it occurs. In addition to x, y, and z, you also need a time coordinate: t. Although this might seem obvious, it didn’t play a large role in physics until the development of Einstein’s relativity, when physicists started thinking about the issue of simultaneity.”

When you describe where you are in the Universe, you typically think of the coordinates you’d need to give to describe your location. This includes an x, y, and z-direction: the three spatial coordinates corresponding to where we live in our three spatial dimensions. But this doesn’t fully tell you everything you’d need to know, because your location is defined not only by your spatial location but when you’re located there: you need a time coordinate, too. If we take a deep look into the relationship between space and time, first put forth by Einstein over a century ago, we’d find that it isn’t even enough to put in an additional coordinate. Time is more than a separate value; it’s every bit as much a dimension as any of the three spatial dimensions.

If you’ve ever wondered why we say that time is the fourth dimension, come read this. It couldn’t be any other way.

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fun-o-physics:

The greek letter π is actually pronounced as “pee” in the Greek language, not as “pie”.

Please make it 314 notes and leave it there. Else we have to take this post to 3141

Update: Ok thanks for the understanding, now we have to make this 3141 🙃🙃

nemfrogfilms: Interference of photons. 1959. …

nemfrogfilms:

Interference of photons. 1959. Physical Science Study Committee.

Internet Archive

The Salmon Cannon Is A Stroke Of Scientific …

The Salmon Cannon Is A Stroke Of Scientific And Environmental Brilliance

“The spectacle of a large fish getting fired out of a cannon has taken the internet by storm. But the Whooshh Fish Transport System uses straightforward physics to solve a complex environmental problem. When placed inside an airtight tube, you can force objects forward by pressurizing air behind it or evacuating the air ahead of it. The pressure gradient exerts a net force on the object inside, accelerating it until it exits the tube. […] A brilliant application by Whooshh Innovations ⁠— to use this technique on salmon ⁠— is solving a pressing environmental problem.”

Hydroelectric dams are some of the most common sources of green energy found anywhere in the world. Although they generate large amounts of clean, renewable energy, they come along with a number of significant environmental impacts. In the Pacific Northwest of the United States, in addition to factors such as lake formation, pollution, waste management, and altering the downstream ecosystem, they also disrupt the upstream runs of spawning salmon. The traditional solution has been to install salmon ladders, but that has limited effectiveness and cannot restore the salmon to their initial, natural runs. Some of the larger dams are simply impassable.

But over the past decade, an innovative solution has emerged: firing the salmon over the dams with a Salmon Cannon. No, for real! Come get the science and see for yourself.

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The greek letter π is actually pronounced as “pee” in the Greek language, not as “pie”.

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I ‘m seriously tryna get hated by every single…

I ‘m seriously tryna get hated by every single one of my followers

Ask Ethan: Where Is The Center Of The Universe…

Ask Ethan: Where Is The Center Of The Universe?

“I am wondering how there isn’t a center of the universe and how the cosmic background radiation is [equally] far away everywhere we look. It seems to me that when the universe expands… there should be a place where it started expanding.”

Ah, the old center of the Universe question. If the Big Bang happened a long time ago, and we see galaxies moving away from us faster and faster the farther away they are, then where did the Big Bang happen? Where did the expansion start?

It seems like such a simple question, but it turns out this is the wrong question to be asking. The way space and the expanding Universe works is very different from the picture most of us have in our heads, which is much more like an explosion than like an expansion. Yet there’s a very large suite of evidence that points us away from an explosion.

Instead of asking *where* the Big Bang occurred, we should be asking *when* the Big Bang occurred. It makes a lot more sense when you think about it in those terms. Come and find out why.