General · Language · Problem

How dark is the universe – optically?

How dark is the universe? Optically – for visible light. Far away from star light and reflected dust. Here’s an interesting perspective on electromagnetic (EM) cosmic energy density – just for optical wavelengths. And without any clarification of fuzzy bounds for a galaxy’s reach. The entire electromagnetic spectrum is another story. • Live Science >… Continue reading How dark is the universe – optically?

Language · Media · Problem

Wavepackets and uncertainty principle

[Preliminary 11-11-2023] [“Quantum foundations” series] Table of contents Context This post was inspired by Don Lincoln’s latest YouTube video (below). Insights from quantum field theory (QFT) have helped me better understand strange aspects of quantum theory [1]. In particular, leaving behind notions of point particles and wave-particle duality, and just going with fields and wavepackets in… Continue reading Wavepackets and uncertainty principle

General · Media · Problem

Island universe RIP – impact of awe-inspiring scales?

Thinking of the latest announcements for Nobel prizes: physics, chemistry, peace … Can the mind-boggling, awe-inspiring scale of the universe improve the odds of our collective survival? An expanding overview effect? “I believe our future depends powerfully on how well we understand this Cosmos in which we float like a mote of dust in the… Continue reading Island universe RIP – impact of awe-inspiring scales?

General · Language · Problem

Does antimatter ‘fall’ the same as matter? – QFT and CPT symmetry

[“Quantum foundations” series – QFT charge inversion] As discussed elsewhere (e.g., in “QFT – How many fields are there?” and comments), in the Standard Model, “there is one field for each kind of particle.” So, consider the positron – the “negative-energy solution” of the Dirac equation. It’s likely that electrons and positrons (anti-electrons) are localized… Continue reading Does antimatter ‘fall’ the same as matter? – QFT and CPT symmetry

General · Media · Quote

Star stuff within us – we are stardust

• “We are stardust, we are golden, we are billion year old carbon” — Woodstock by Joni Mitchell as performed by Crosby, Stills, Nash & Young. • Space.com > “Are we really made of ‘star stuff’ and what does that even mean? (video)” by Robert Lea (August 21, 2023) – These inspiring words from Carl… Continue reading Star stuff within us – we are stardust

General · Language · Media · Problem

The degree of entanglement – quantifying an entangled system

INTRODUCTION Remember pet rocks? So, what if someone gave you a gift, claiming it was even better than a Moon rock or Mars pebble. Something almost magical. An expensive novelty item. As advertised on TV: “Tangled Blocks” … go quantum! do Einstein spooky action! each block contains a particle entangled with one in the other… Continue reading The degree of entanglement – quantifying an entangled system