You're missing the point. For one thing I'm not saying it's good or wise, I'm only saying that "we would have developed tech to have radio broadcast in non interfering ways" is not invalid physics and was not at least when VHF/FM broadcast stations appeared. The mistaken assumption about "non-interfering ways" was that some kind of prevention of interference would have been invented for multiple stations operating on the same channel both in-range of a single receiver. Prevention of interference is also possible if stations can be kept on dedicated channels such that none do interfere with each other and that's been easy to implement for decades. It's also NOT self-registration and I wasn't suggesting NO-registration. In fact I was suggesting forced registration of transmitter availability by restricting retail sales of receivers, i.e. broadcasters would comply with a limited set of rules to be compliant with available receivers but otherwise could do what they wanted. The "registration" I suggested doesn't require any part of the broadcaster's identity to be provided. It can be as little as a 5 to 10s "jingle" style audio content at 5kHz mono that identifies the station's broadcast intentions and what channel it plans to operate on. For example, in the following quote apply a music background with the words before the colon sung by a set of three women in harmony and after the colon spoken by a deep voice male "Radio murder : The station with 24 hour live killings on-air", It's not necessary to have the frequency stated in the "jingle", it can be handled easily with a sub-audible tone set that identifies all the known channels and a single one used at station registration and listener channel selection to identify what frequency the station is or will be on. With enough channels then the gang idea fails because the band is large enough to permit listening to something else. The registration is limited to on-air availability of any station and channels become free as stations go off air, i.e. it's not "registration" in the same sense as is currently used.

That's not without restrictions (there's a limit to geographic station density) but "non-interfering ways" doesn't have to imply stations avoid interference while being on the same or overlapping channels, it can also mean stations are guided automatically into idle channels in a way that avoids interference.

Your mistake is assuming that the entire implementation of broadcast radio "bands" would be no different from the implementation of the present AM and FM broadcast bands under the OP's suggestion. There is NO invalid physics in the OP's suggestion, I have been able to do most of what's needed on my ham rigs for decades. It would actually require very little difference to the model of the current bands themselves to implement what the OP is talking about. For example, in the USA if in the 1960's (or whenever VHF/FM stations appeared) the FCC had decided to permit VHF/FM broadcast but didn't want to have any meaningful regulation of broadcast stations it could have worked with the departments that regulate cars and retail purchases so that the only legal receivers that could be found and purchased by "listeners" in the USA had a simple extra feature then the OP's suggestion is easily implemented. All of the broadcast stations (regardless of funding size) would implement stations that were compatible with in-use receivers. So, if receivers operated by "finding" a station by allowing the listener to hear a list of station info currently on-air via a single frequency area registration service (provided as cheaply as possible to the FCC and at no cost to broadcasters and listeners) then the receiver switches to the current on-air broadcast frequency for the station selected by the listener. If that existed then all stations would implement transmitters that would contact the local "registration" stations, register themselves and either be directed to or indicate the transmitter frequency they planned to operate on and begin their transmissions. The registration doesn't have to require any rules (other than compliance with other national laws, i.e. stations that broadcast murders would only be allowed to do so as acts or their output could be used against their operators in court). Back in 1960 (or when VHF/FM was introduced), the registration station might allow 5 to 10s of "station jingle" at 5kHz mono to be provided by the broadcast station and that would be assembled into the station list the listeners would receive via audio recording at the registration station (originally on tape). All directions to actual broadcast channels could be done using something as simple as a sub-audible frequency tone-code overlayed on each "jingle" in the list. Some scanning of the band for what can be received currently allows channels to be "released" automatically at the registration station. The total bandwidth of the registration station would have to exceed 5kHz and there might need to be multiple registration channels to avoid interference but otherwise the technology for all of this was available when VHF/FM broadcast was introduced and it leaves a large part of the band for deployment at random when stations want to go on-air. We still haven't specified any modern style (digital data) coding but it could all be upgraded to digital station registration and selection in the 1990's or later without damaging existing receivers.

It isn't necessary to get around the laws of physics. In a world with no regulation of useful radio waves live VHF and modulation schemes that permit about 20kHz of stereo music we would have cheaply developed something like an on-air registration service on a fixed frequency (or that was easy to find on-air) that allows random stations to launch their transmitter, register it with some info for receivers and operate on a quiet frequency in the band. Then end-users would start a receiver that looked at the registration service for something interesting to listen to and tune to it's registered frequency. i.e. What the OP suggested.

As most posters note, there is never a direction from which the earth isn't transiting the sun. Therefore, a single location on the surface of earth for a laser other than perhaps either pole is not a practical implementation anyway since it will be on the sun facing side of earth about half the day. It will not be able to mask the transit taking place while it is on the daytime side of earth. You couldn't fire 30MW visible light lasers into the sky from earth without the massive objection of at least aviation. The "visible" light from the sun isn't a flat spectrum anyway, any laser system that didn't replicate the spectrum of the solar radiation (visible and invisible) wouldn't be a mask to anyone capable of observing the transit in the first place. Then, so what! There's nothing special about the earth transit of the sun that says to any aliens "here be a food or war source". Each of the other planets in the solar system is also at any instant in transit of the same sun when observed from some direction. You might be able to say because of the spectrum filtering what the atmosphere of a transiting planet is made of but which scientists assume there's anything special about an atmosphere of nitrogen with a bit of oxygen to aliens? Which scientists assume that all aliens are of a similar composition to humans (by saying that masking ourselves from aliens at all only requires masking the solar transit of earth within the solar system while there is continual RF energy from earth radio stations anyway). Any aliens capable of coming over from their planet to the solar system for a fight/feed (i.e. the definition of what we want to mask ourselves from) are, given our current capabilities of carrying out war in space, just as likely to hook (insert your choice of solar system planet) to a tow hook and take it back to their own home as a source of raw materials leaving us bewildered at a vanishing planet while they laugh at the ease of the exercise. Nope, it was a decent and entertaining April Fool joke by Kipping and Teachey from Columbia University but no more.

In many countries firing lasers in any format of away from the surface of earth would require co-ordination with the national aviation administration agency. Clearly flying aircraft through the beam of a 30MW visible light laser would be a lot worse than having a laserpointer aimed at them by kids. I heard this all day on April 1st on NPR and the BBC. Although the BBC news site dates it March31st I doubt the story is anything more than an April Fool joke by the original authors.

There is never no direction from which the earth is not currently transiting the sun. April Fool.

What's that current ad that starts with the question: "Constipated?" I can't wait until some show has as a placement the product that's for. Plus, the ad I'm thinking of shows a handful of features it has so if it became the Hawaii Five O season laxative some year they could show a different feature in different episodes just like they do with the cars. Same goes for a show that has a season ED medicine some year. That would be great if they also showed the side-effects as well and there was the character with the four-hour-boner worked into the plot who did the right thing and consulted his doctor.

...in the case of religion perhaps. Science on the other hand plainly advances because it has advanced, often even in the presence of a single soul with an alternative opinion (not consensus plainly). Some of the greatest rewards in science appear to be seeking out individuals like that especially (aiming at creating new consensus from individuals with the courage to explore). IOW, if there is any consensus in science then you are only describing a limited set of cases of consensus and not all cases having it, particularly not science it seems.

But that hasn't yet stopped someone who feels the evidence has problems from expanding the science in some way and changing the direction. The governments of most of us have little interest in not expanding science honestly, the same goes for other funders of research. The US government can't wait for it's own discovery of interstellar transport at little cost. It doesn't care what science is done honestly. The ones who have cheated have been individual scientists who found a way to obtain income for nothing. Those cases that have been reported where people have been found lying for funding have resulted in very severe outcomes for the liar. Whatever there is in the way of consensus in sciences doesn't undermine their honesty or progress. The group who do behave the way you describe are the chaplains. Let's say there is a god, the Christian faiths are finished exploring it because it is already all defined in full.

The prosthetic must have two selectable operations so that his run can be guaranteed to be so balanced and he also does well to ensure that he always launches the jump from the prosthetic. At the end of the day, if there has to be a new competitive division for those with a prosthetic then his most important goal is to avoid it being a lower athletic standard than the ones he divides from so good luck to him in trying to avoid it being called paralympics or equivalent.

Rehm might go faster than naturally legged racers in the 100m circle.

That part is not fair. The other day when I got hooked on watching large building controlled explosion demolitions (implosions) were it not for a local Las Vegas TV station's news department's one hour coverage of it I would not have discovered the superb footage of the thirty second downing of the Alladin with the inclusion of sacrificial cameras. I love you balcony cam!

Indeed, most drawings I can think of can be reproduced by moving the drawing device using only two directional references regardless of how thick the material placed on the paper is. Therefore, the drawing is two dimensional in a real sense even though it is simultaneously three dimensional in terms of deposit of crayon, pencil, chalk, ink, etc.

Correction: I used transistor in places I meant to use atom: None of the materials the transistor is made of is a few atoms thick. Read the story more carefully. There was never a claim that the transistor was 2D, only that each of the materials the transistor used multiple layers of was 2D. Well, even an atom is thick but it is also true that in each layer of the materials used in the transistor the position of any atom with respect to any other atom only requires two dimensions to describe it (right a couple of atoms and forward a couple of atoms, no third direction required for each material used).