David Alger

Software Engineer, Triathlete

[Programming Wisdom @CodeWisdom]

"You don't pay engineers to write code, you pay them to understand subtleties and edges of the problem. The code is incidental." – Ted Dziuba

[sysxplore @sysxplore]

Linux file permissions for beginners

[⭐️ butters 🍜 @NoisyButters]

*NEW VID* i hav to talk about this (any and all feedback surrounding this is heavily appreciated) 💛

https://t.co/cng7g6Acsg
https://t.co/cng7g6Acsg
https://t.co/cng7g6Acsg

[Curiosity @CuriosityonX]

The universe is expanding faster than physics can explain.

Astronomers have confirmed something that may rewrite the laws of cosmology: the universe is expanding faster than our physics can explain.

This is the “Hubble Tension” – a persistent disagreement between two precise ways of measuring the expansion rate of the universe, known as the Hubble constant.

One method looks at the cosmic microwave background (CMB) – the oldest light in the universe, dating back to just 380,000 years after the Big Bang. Using data from the Planck satellite, scientists extrapolate a value of about 67 km/s per megaparsec (how fast galaxies recede per unit of distance). This represents the early universe.

The second method observes Cepheid variable stars – pulsating stars whose brightness allows us to measure cosmic distances with high accuracy. By building a “cosmic distance ladder,” astronomers can measure how fast nearby galaxies are moving away today. This gives a faster expansion rate: about 74 km/s per megaparsec.

The two values shouldn’t be this far apart. For years, some thought Hubble’s data was skewed by background star contamination. But with James Webb’s sharper resolution, scientists remeasured over 1,000 Cepheid stars in five galaxies and confirmed: Hubble’s numbers were right.

That means the mismatch is real – not an error.

If both methods are correct, our current model of the universe – ΛCDM – is incomplete. It may mean there’s a new particle or field we haven’t discovered, or that dark energy behaves in unexpected ways.

Learn more:
"James Webb telescope confirms there is something seriously wrong with our understanding of the universe." LiveScience, 2024.

[Black Hole @konstructivizm]

Only nerds will know what this is.

[David Alger @DAlgerODU]

@lina_nekita1

[David Alger @DAlgerODU]

@lina_nekita1

[David Alger @DAlgerODU]

@NoisyButters I agree, along with camera shake - some of those make me want to hurl lunch

[Linux Handbook @LinuxHandbook]

💡 Linux tip of the day

Use brace expansion with mkdir -p to create multiple nested directories in one go!

This oneliner

$ mkdir -p projects/{frontend,backend}/{src,test,docs}

will create 6 directories instantly 👇

[Eyo Eyo, PhD @Eyowhite3]

Python Data Visualisation cheatsheet.

[Black Hole @konstructivizm]

The heliosphere protects the solar system from cosmic radiation.

[sysxplore @sysxplore]

Some handy Linux commands you must know

[sysxplore @sysxplore]

Bash Scripting Basics

[sysxplore @sysxplore]

Resources to learn Linux

[The Elder Scrolls Online @TESOnline]

No more monkey business! 🐒 Unlock the 10-Year Anniversary Monkey pet at https://t.co/bKjqWTCd6r or in the Crown Store using the reward code: 2025ESODirect.

[Tom Sydney Kerckhove @kerckhove_ts]

SQL was made "so that even business people could make database reports" only to find out that business people don't want to do that and will still ask programmers.

LLMs were made "so that even non-technical people could program"...

[sysxplore @sysxplore]

Digital signatures crash course

[sysxplore @sysxplore]

How does git work?

[sysxplore @sysxplore]

How docker works crash course

[Aesthetics 𝕏 @aestheticsguyy]

Art wallpaper 🖼️