Why can't we transplant other animals’ eyes into humans and gain the benefits of their eyes? Answer by Ken Saladin, former professor of histology: 'We can't even transplant a human eye into another person and restore vision.'

Once I read a description to a numerical methods course and it says 'often in math, it is possible to prove the existence of a solution to a problem but it isn't possible to 'find it'. What does that mean? Answer by Senia Sheydvasser qr.ae/psHGic with a game example.

A modern CPU with billions of transistors, when running a normal program, how many of those transistors are actually used? Answer by Joe Zbiciak: 'Chips and software both have bugs, and chips have manufacturing defects.'

Why can't a physicist make quantum physics understandable to most people? Answer by Mark John Fernee, 20+ years as a physicist: ''Quantum objects are neither particles nor waves. They have behaviors that can be consistent with either.'

Was Einstein too old to work at Los Alamos during the Manhattan Project even if he had security clearance? Answer by Viktor T. Toth: 'E = mc² entered the public imagination as though it was this equation that unlocked the secret of nuclear physics. It was not.'

What happened to satellite pictures, why aren't they used to solve some of the worst crimes? I thought they can read a license plate from space. Answer by Dr. Balaji Viswanathan: 'A high resolution spy satellite doesn’t usually cover more than a couple of square kilometers...'

What does Alan Kay think about programming and teaching programming with copilots and LLMs of today? Answer by Alan Kay: 'A simple principle is that for most things that are automated and scaled, the *trust requirements* have to be vastly expanded and made vastly more strict.'

Do antidepressants just cover up the underlying problems? Answer by Jack J. Wu, M.D.: 'In my psychiatry residency training back in 2004–2008, even in the psychiatrist/psychiatry realm we thought that antidepressants, ... were just covering up the underlying problems...'

From an engineering standpoint, is there a theoretical limit to the maximum height of a skyscraper? Answer by Doug Graham: 'Yes, but we’re a long way from reaching it.'

What is understanding of the mysterious dimensionless fine structure constant of circa 137? Answer by Michael Peskin, Professor at Stanford University's SLAC National Accelerator Center: '... the same way that the fact that the Moon and Sun have the same angular size...'

What is the estimated fuel consumption of a starship trip from NRHO to Mars? Answer by Frank Norris, Author of 'Colonizing Mars': 'As far as the trip to Mars that is not too much of a challenge. Starship can manage about 64 tons of payload to Mars orbit and back to Earth...'

If a defibrillator is not present, could you use a 110 outlet restart a stopped heart? Answer by Marc Boutet, Paramedic who helps out with Research on Cardiac Arrest:

'An electrical shock from a defibrillator does not restart a stopped heart.

It actually stops the heart.'

Why is it when I see a propeller on a single engine plane looks it's bending outward away from the plane? Answer by Scott Hanson, Former Electronic Warfare Technician at United States Navy: 'What you are referring to is called the rolling shutter effect! ...'

Why are movie budgets so high? Answer by Royce Allen Dudley, Producer, Director, Cinematographer: '...much of the crew worked yesterday or longer arranging the shoot and prepping and loading gear trucks, picking up supplies and so forth. Just for one shot.'

Why is the four color theorem important? Answer by Senia Sheydvasser, PhD in Mathematics: '...four colors always suffice, regardless of what the map is. But this might yield the erroneous impression that, at its core, the four color theorem is about map-making'

What animal do you think looks like it's from a different planet? Answer by Gary Meaney, author of Zoology's Greatest Mystery: 'They challenge our very idea of what an organism even is - and what it isn’t.'

Can a single virus particle infect a human? Answer by Dr Jo: 'The risk of actually getting ill from that single virion is perhaps slightly less, and for a 50% chance of disease, you likely need about 1000 copies...'

Why do some planes have propellers facing backwards, and some have them facing forwards? Answer by Mason Bivens, aeronautical engineer:

There are good reasons that most aircraft have tractor propeller configuration (propellers face forward).

The reason’s aren’t intuitive, so…

How do economists measure the broader social impacts (economic growth, health outcomes, etc.) of schooling? Alex Eble, Associate Professor of Economics and Education Columbia University, Teachers College, Columbia University, explains here: quora.com/How-do-economi…

How do retail prices adjust to seasonal demand peaks, and what factors influence these changes? Boyoung Seo, Assistant Professor at Indiana University, shares her insights here: quora.com/How-do-retail-…