Recent comments in /f/Futurology

MarksmanKNG t1_j9eiitc wrote

Agreed on this. It provides a baseline foundation which can be comforting to the common layman at first glance.

But devil's in the details and as shown in his novels, there are a lot of details in a big spider web. And those details goes in both ways in more than one.

I'm hoping to pursue further in this with my own writing following Isaac Asimov's track. Truly a man of his time.

3

FuturologyBot t1_j9egadp wrote

The following submission statement was provided by /u/esprit-de-lescalier:


The interference pattern is a supremely strange result because it implies that both of the particle’s possible paths through the barrier have a physical reality.

The path integral assumes this is how particles behave even when there are no barriers or slits around. First, imagine cutting a third slit in the barrier. The interference pattern on the far wall will shift to reflect the new possible route. Now keep cutting slits until the barrier is nothing but slits. Finally, fill in the rest of space with all-slit “barriers.” A particle fired into this space takes, in some sense, all routes through all slits to the far wall — even bizarre routes with looping detours. And somehow, when summed correctly, all those options add up to what you’d expect if there are no barriers: a single bright spot on the far wall.

It’s a radical view of quantum behavior that many physicists take seriously. “I consider it completely real,” said Richard MacKenzie, a physicist at the University of Montreal.

But how can an infinite number of curving paths add up to a single straight line? Feynman’s scheme, roughly speaking, is to take each path, calculate its action (the time and energy required to traverse the path), and from that get a number called an amplitude, which tells you how likely a particle is to travel that path. Then you sum up all the amplitudes to get the total amplitude for a particle going from here to there — an integral of all paths.

Naïvely, swerving paths look just as likely as straight ones, because the amplitude for any individual path has the same size. Crucially, though, amplitudes are complex numbers. While real numbers mark points on a line, complex numbers act like arrows. The arrows point in different directions for different paths. And two arrows pointing away from each other sum to zero.

The upshot is that, for a particle traveling through space, the amplitudes of more or less straight paths all point essentially in the same direction, amplifying each other. But the amplitudes of winding paths point every which way, so these paths work against each other. Only the straight-line path remains, demonstrating how the single classical path of least action emerges from unending quantum options.

Feynman showed that his path integral is equivalent to Schrödinger’s equation. The benefit of Feynman’s method is a more intuitive prescription for how to deal with the quantum world: Sum up all the possibilities. Sum of All Ripples

Physicists soon came to understand particles as excitations in quantum fields — entities that fill space with values at every point. Where a particle might move from place to place along different paths, a field might ripple here and there in different ways.

Fortunately, the path integral works for quantum fields, too. “It’s obvious what to do,” said Gerald Dunne, a particle physicist at the University of Connecticut. “Instead of summing over all paths, you sum over all configurations of your fields.” You identify the field’s initial and final arrangements, then consider every possible history that links them.

Feynman himself leaned on the path integral to develop a quantum theory of the electromagnetic field in 1949. Others would work out how to calculate actions and amplitudes for fields representing other forces and particles. When modern physicists predict the outcome of a collision at the Large Hadron Collider in Europe, the path integral underlies many of their computations. The gift shop there even sells a coffee mug displaying an equation that can be used to calculate the path integral’s key ingredient: the action of the known quantum fields.

“It’s absolutely fundamental to quantum physics,” Dunne said.

Despite its triumph in physics, the path integral makes mathematicians queasy. Even a simple particle moving through space has infinitely many possible paths. Fields are worse, with values that can change in infinitely many ways in infinitely many places. Physicists have clever techniques for coping with the teetering tower of infinities, but mathematicians argue that the integral was never designed to operate in such an infinite environment.

“It’s like black magic,” said Yen Chin Ong, a theoretical physicist at Yangzhou University in China who has a background in mathematics. “Mathematicians are not comfortable working with things where it’s not clear what’s going on.”

Yet it gets results that are beyond dispute. Physicists have even managed to estimate the path integral for the strong force, the extraordinarily complex interaction that holds together particles in atomic nuclei. They used two main hacks to do this. First, they made time an imaginary number, a strange trick that turns amplitudes into real numbers. Then they approximated the infinite space-time continuum as a finite grid. Practitioners of this “lattice” quantum field theory approach can use the path integral to calculate properties of protons and other particles that feel the strong force, overcoming rickety mathematics to get solid answers that match experiments.

“To someone like me in particle physics,” Dunne said, “that’s the proof that the thing works.” Space-Time = The Sum of What?

The greatest mystery in fundamental physics, however, sits beyond experimental reach. Physicists wish to understand the quantum origin of the force of gravity. In 1915, Albert Einstein recast gravity as the result of curves in the fabric of space and time. His theory revealed that the length of a measuring stick and the tick of a clock change from place to place — that space-time is a malleable field, in other words. Other fields have a quantum nature, so most physicists expect that space-time should too, and that the path integral should capture that behavior.


Please reply to OP's comment here: https://old.reddit.com/r/Futurology/comments/117ym4h/how_our_reality_may_be_a_sum_of_all_possible/j9edotc/

1

FuturologyBot t1_j9efkh8 wrote

The following submission statement was provided by /u/esprit-de-lescalier:


https://archive.is/dBUUu

Efforts to increase productivity hold lessons for sceptics, too

If Liz Truss can compress a whole premiership into seven weeks, why can’t a standard working week be squashed into something more compact? A six-month pilot scheme, in which around 3,300 workers from 70 companies are testing out a four-day workweek, is due to conclude this month. Proponents say a shorter week delivers a better work-life balance without hurting overall output. Like previous such experiments, it is likely to be hailed a success. A mid-point survey by the trial’s organisers—researchers at the universities of Oxford and Cambridge and Boston College, the 4 Day Week Campaign, a non-profit, and Autonomy, a British think-tank—found that the transition had worked well for 88% of surveyed companies.

Sceptics might observe that the companies involved are self-selecting. Roughly one in five employers who had signed up dropped out before the pilot began, according to the 4 Day Week Campaign. Most of the participants that remain are smaller companies, many of them agencies specialising in management and technology. They also include charities.

But the scheme holds useful lessons about productivity. In particular a four-day week forces firms to think harder about time management. Most businesses in the trial have encouraged employees to leave meetings when they are not contributing, and to be more selective about accepting invitations. Daryl Hine of Stellar, an asset-management company in London, calls this a “diary detox”. This also extends to reducing commutes.

Of the participating organisations, 46% reported maintaining overall output at the same level, and 49% said it had improved. The trial’s largest company, Outcomes First Group, a children’s education and care provider, tracks indicators for its 1,027 participating employees. Its hr department has goals for response time to emails; it staff are given so-called net promoter scores, which track how colleagues rate their services. On both counts, they have made “rare” leaps, says Sharon Platts, the company’s chief people officer. Participants say that their employees feel more motivated. Plenty use the extra day to get errands out of the way before the weekend.

Becoming a four-day operation can be hard in a five-day world, however. Bookishly, an online shop, chose Wednesdays off to avoid having three days in a row when packages are not mailed out; people are warned about the new schedule before they order. But customers are not always prepared to wait, so most firms in the scheme have tried to spread staff more thinly. Platten’s, a fish-and-chip shop in Norfolk, gives its 50-or-so employees two days on and two days off to cover the week. Shifts overlap at busy periods, but organising training and team events has become trickier as a result.

More tests are on the horizon. In January South Cambridgeshire District Council will become the first British local authority to try out a four-day week. The lessons learned are likely to be valuable even if the idea does not spread. Mr Hine says that if performance slips, “gift days” will be rolled back. In busier periods employees may need to come in more. But in one way or another, he says, a slimmer work schedule is “here to stay”. ■7

For more expert analysis of the biggest stories in Britain, sign up to Blighty, our weekly subscriber-only newsletter.

This article appeared in the Britain section of the print edition under the headline "On the fifth day, errands"


Please reply to OP's comment here: https://old.reddit.com/r/Futurology/comments/117yj5w/a_pilot_scheme_to_trail_the_fourday_workweek_in/j9edbgu/

1

esprit-de-lescalier OP t1_j9edotc wrote

The interference pattern is a supremely strange result because it implies that both of the particle’s possible paths through the barrier have a physical reality.

The path integral assumes this is how particles behave even when there are no barriers or slits around. First, imagine cutting a third slit in the barrier. The interference pattern on the far wall will shift to reflect the new possible route. Now keep cutting slits until the barrier is nothing but slits. Finally, fill in the rest of space with all-slit “barriers.” A particle fired into this space takes, in some sense, all routes through all slits to the far wall — even bizarre routes with looping detours. And somehow, when summed correctly, all those options add up to what you’d expect if there are no barriers: a single bright spot on the far wall.

It’s a radical view of quantum behavior that many physicists take seriously. “I consider it completely real,” said Richard MacKenzie, a physicist at the University of Montreal.

But how can an infinite number of curving paths add up to a single straight line? Feynman’s scheme, roughly speaking, is to take each path, calculate its action (the time and energy required to traverse the path), and from that get a number called an amplitude, which tells you how likely a particle is to travel that path. Then you sum up all the amplitudes to get the total amplitude for a particle going from here to there — an integral of all paths.

Naïvely, swerving paths look just as likely as straight ones, because the amplitude for any individual path has the same size. Crucially, though, amplitudes are complex numbers. While real numbers mark points on a line, complex numbers act like arrows. The arrows point in different directions for different paths. And two arrows pointing away from each other sum to zero.

The upshot is that, for a particle traveling through space, the amplitudes of more or less straight paths all point essentially in the same direction, amplifying each other. But the amplitudes of winding paths point every which way, so these paths work against each other. Only the straight-line path remains, demonstrating how the single classical path of least action emerges from unending quantum options.

Feynman showed that his path integral is equivalent to Schrödinger’s equation. The benefit of Feynman’s method is a more intuitive prescription for how to deal with the quantum world: Sum up all the possibilities. Sum of All Ripples

Physicists soon came to understand particles as excitations in quantum fields — entities that fill space with values at every point. Where a particle might move from place to place along different paths, a field might ripple here and there in different ways.

Fortunately, the path integral works for quantum fields, too. “It’s obvious what to do,” said Gerald Dunne, a particle physicist at the University of Connecticut. “Instead of summing over all paths, you sum over all configurations of your fields.” You identify the field’s initial and final arrangements, then consider every possible history that links them.

Feynman himself leaned on the path integral to develop a quantum theory of the electromagnetic field in 1949. Others would work out how to calculate actions and amplitudes for fields representing other forces and particles. When modern physicists predict the outcome of a collision at the Large Hadron Collider in Europe, the path integral underlies many of their computations. The gift shop there even sells a coffee mug displaying an equation that can be used to calculate the path integral’s key ingredient: the action of the known quantum fields.

“It’s absolutely fundamental to quantum physics,” Dunne said.

Despite its triumph in physics, the path integral makes mathematicians queasy. Even a simple particle moving through space has infinitely many possible paths. Fields are worse, with values that can change in infinitely many ways in infinitely many places. Physicists have clever techniques for coping with the teetering tower of infinities, but mathematicians argue that the integral was never designed to operate in such an infinite environment.

“It’s like black magic,” said Yen Chin Ong, a theoretical physicist at Yangzhou University in China who has a background in mathematics. “Mathematicians are not comfortable working with things where it’s not clear what’s going on.”

Yet it gets results that are beyond dispute. Physicists have even managed to estimate the path integral for the strong force, the extraordinarily complex interaction that holds together particles in atomic nuclei. They used two main hacks to do this. First, they made time an imaginary number, a strange trick that turns amplitudes into real numbers. Then they approximated the infinite space-time continuum as a finite grid. Practitioners of this “lattice” quantum field theory approach can use the path integral to calculate properties of protons and other particles that feel the strong force, overcoming rickety mathematics to get solid answers that match experiments.

“To someone like me in particle physics,” Dunne said, “that’s the proof that the thing works.” Space-Time = The Sum of What?

The greatest mystery in fundamental physics, however, sits beyond experimental reach. Physicists wish to understand the quantum origin of the force of gravity. In 1915, Albert Einstein recast gravity as the result of curves in the fabric of space and time. His theory revealed that the length of a measuring stick and the tick of a clock change from place to place — that space-time is a malleable field, in other words. Other fields have a quantum nature, so most physicists expect that space-time should too, and that the path integral should capture that behavior.

12

snapcracklethenpop t1_j9edocg wrote

I agree

Many young people on Reddit who don’t shit about shit, have never traveled to a third world or developing country and it shows, romanticize European countries and what could be but political realities are all too real in each country.

Every country has their own pile of shit they deal with everyday. On it’s worst day, America is still better place to wake up on than most. I’m a first generation American and my parents are immigrants. I’m raising children here and understand the fears and of course have reservations about the future but I gotta say, the grass isn’t always greener

2

urbinorx3 t1_j9edngf wrote

Agreed, but keep in mind the early stages of pc/console gaming were also expensive. This is early adopters territory we’re in, we’re underserved in hw, guis and actual use cases. But by exploring and innovating with an engaged user base there’s a chance a killer combination is discovered, one that is enticing enough for an early majority to jump in. Do remember how crappy and expensive early consumer pc’s were

0