This week’s new questions

Is sweat from a different cause – exercise, anxiety or illness – chemically unique and can dogs tell the difference? And how could I theoretically reach other dimensions in the multiverse if they exist?

23 November 2022

A man holds his lurcher dog as the canine excitedly licks and nuzzles with a woman who smiles and strokes the pet. — Catherine Falls Commercial/Getty Images

Is sweat from a different cause – such as exercise, anxiety or illness – chemically unique? Can dogs tell the difference?

Cathy Tupper,

Coniston, Cumbria, UK

Neon portal in the foggy forest, magical evening; Shutterstock ID 2116865828; purchase_order: -; job: -; client: -; other: - — Shutterstock/Martin Capek

How could I theoretically reach other dimensions in the multiverse if they exist?

Griff Sullivan,

London, UK

To answer this question – or ask a new one – email lastword@newscientist.com.

Questions should be scientific enquiries about everyday phenomena, and both questions and answers should be concise. We reserve the right to edit items for clarity and style. Please include a postal address, daytime telephone number and email address.

New Scientist Ltd retains total editorial control over…