# Category Archives: Physics

## Negative Mass Part II

I finally finished the follow up video to my discussion of negative mass for the Summer of Math Exposition. Check it out.

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## New Video: What Does Negative Mass Mean? Part 1

Grant Sanderson, of the excellent 3Blue1Brown math YouTube channel, has set up a contest for new creators to make math videos, called the Summer of Math Exposition. Well, this isn’t my first math video, but in the spirit of the … Continue reading

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## The Science of Project Hail Mary

Andy Weir’s latest book, Project Hail Mary, is a very good hard science fiction tale about a journey to another solar system in search of a way to save Earth from disaster. Mr. Weir always does mostly pretty good science … Continue reading

Posted in Physics, Science Fiction, Story Analysis | | 5 Comments

## A Study in Parallel Universes: the Diproton “Catastrophe”

Advocates of “fine-tuned universe” claim that if the physical laws of our universe were just slightly different, life would not be able to exist. Some of my colleagues and I previously looked at these claims with the “Weakless Universe,” where … Continue reading

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## What Is the Equation for the Strong Nuclear Force?

Previously, I described how the weak nuclear force really is a force even though it’s almost never described as one. Instead of a simple inverse square law like gravity and electromagnetism, it decays exponentially so that it weakens over a … Continue reading

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## How Is the Weak Nuclear Force an Actual Force?

It’s time for another physics explainer. In an earlier post, I explained Lagrangian mechanics and why it uses the weird (to physicists) equation L=T-V. I thought I might do some more posts like that, and I found a topic that … Continue reading

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## Essay: The Real Problem with “The Cold Equations”

As part of tomorrow’s episode of A Reader’s History of Science Fiction, I felt the need to write a companion essay analyzing one of the most famous (or perhaps infamous) short stories in the history of the genre: “The Cold … Continue reading

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## Why does the Lagrangian equal T-V?

And here’s one for the category of “Posts where you need a degree in physics to even understand the question.” Okay, there are probably a fair number of you who don’t have a degree in physics who can understand this … Continue reading

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