Would it make sense for you to fly West from SFO, turn around, go super-sonic over the ocean and fly towards NY — then again, decelerate over the Atlantic, and turn back?
i.e. what is the distance from the shore you can boom?
I understand why you got downvoted, but I don't think the question was actually repellant. If it were at the top of the thread it would be annoying but here I find it a fun thought experiment.
Didn’t get down-voted overall so fine on that end.
I actually never though of the existence of a continuous cone of focus outside of the plane — the graph I had seen were all focused on the whether the plane heard it.
I guess an alternative option would be to find routes above the polar circle, or through the narrow of Central america — but the increased distance would make it less interesting at “just” Mach 2.2.
The sonic boom isn't created when the aircraft transitions through the speed of sound. Although I never hear it explained this way, I believe it is caused when the velocity of the aircraft with respect to the listener transitions the speed of sound. That's when the sound waves approaching the listener bunch up and cause the boom.
When the aircraft is directly above a listener on the ground, the relative velocity is zero, so you can see how the velocity changes from greater-than-sound to less-than-sound (twice) as the aircraft is approaching and then departing with respect to the listener. Thus the listener hears 2 booms.
The boom is usually explained in terms of shock waves emanating from the aircraft, but I think my description explains the phenomenon just as well, but more intuitively.
slight correction to the above: there is no second boom heard by the listener when the aircraft is flying away from the listener faster than the speed of sound. The listener the would simply hear no sound.
As others have said, the boom is continuous. However, what you could (and presumably would) do is gain altitude at sub-sonic speed, then go supersonic only once cruising altitude is reached. That should help with volume. Also presumably they would avoid flying over major population centers.
Possibly! Certainly if the plane was traveling in a vacuum it would produce no boom, so one would assume that the boom would be reduced as the air became less dense. However my understanding is that most of the advantage from altitude comes from the attenuation (or really spreading out) of sound with the square of distance.
Might be an idea to spend a little more time on that.
The engineering is not the hard part here.
Without regulatory support and approval you don't have a product or a market, so "Let's worry about that after we get the prototype working" may not be a fully viable strategy.
Here is what I have done many times when a telemarketer calls I listen to what he wants to sell, the I say: “Yes, I think I’ll be interested in this, can you hold on just a bit?” Then I put down the phone and let him wait. Many times, the caller was still waiting 5 minutes later.
Some of them are paid/incentivized for their talk time, so the reps will be perfectly happy, in fact GLAD, to be put on endless hold, because they can mute their headset, kick back and talk to their friends while all the time their metrics look good and it looks like they're working.
Some of our reps at my old company would purposely change our AI to dial places like Medicare or social security so they could purposely get put on endless hold.
The difference between socialism and communism was all in the "communist" propaganda. All east-european countries were "socialist" with the almost utopian goal of becoming "communist". It's a label that could be changed at anytime by the leaders.
Technically, according to the doctrine, socialism was "everybody contributes based on ability, and receives based on the contribution", while communism was: "everybody contributes based on ability, and receives based on their needs", which was utopian. Western countries did not (want to) grasp the difference, so they just called the eastern block "communist".
Under those definitions, isn't most of "socialist Europe" not really socialist? I mean a lot of countries have got a safety net and welfare programs and all that which seemingly are standardized, not indexed to your previous income. So you pay in with taxes that are based on what you make (and thus you contribute based on ability).
Or is the idea that you keep a portion of your pay after taxes the "receives based on contribution" portion?
You have to understand that those were just slogans, with almost no practical equivalent. Corruption was rife, and taxes were almost unheard of. You get a salary (cash) and pay for goods with cash. No taxes on either end or annual tax return. Unemployment was officially inexistent, (you could go to jail if you had no job), therefore no welfare programs existed. Socialist parties in Western Europe had no clue about what they were wishing for.
I'll throw in the response that the "socialist" countries of Europe are socialist to varying degrees, and I don't think most of them actually consider themselves socialist. Unlike the US, most western countries think things like a social safety net and universal health care are good ideas in and of themselves, and do not necessarily ascribe any particular political ideologies to the ideas.
Also, ideally, you don't want to add length to width, or Hertz to Becquerel (both have [1/sec] unit).
This was my humble attempt to address this with a Scala Units library: https://github.com/adrianfr/scalau
No, you add the lengths of the sides. That's type-safe and generalizes from rectangles with edges parallel to the x and y axes to general polygons:
perimeter = poly.edges.map(length).sum()
Height and width have (implicit) direction; length doesn't.
But yes, this will get hairy. For convenience, you want the ability to add heights, but that only makes sense in some cases. Two 100m high skyscrapers only make a 200m high skyscraper if you place one on top of the other.
Or maybe you want to find the height of an average skyscraper so you want to add and then divide. This is going too far maybe. At some point, one has to accept that not all logic bugs are type errors, and not all type errors are common enough in practice to worry about. I have no idea where that point is, but I'm sure it exists.
If the City needs teachers, social workers and others with traditionally lower wages, wouldn't it make sense that their wages would also go up (based on demand) if the rent control goes away?
Bingo, the most important question that is not being discussed.
This whole discussion is a social class issue. The folks there have defined their upper class and they actively don't want lower class people there.
Otherwise, if you insist on hyperinflation of tech salaries and hyperinflation of property prices, there's no reason not to glorify a similar hyperinflation in teachers salaries or a hyperinflation in social worker salaries. But no, there's agony and terror that a lower class human might soil our pristine streets if we paid them a living wage...
Have you considered that it's simply a case where an unprivileged group is unhappy with being denied access to a good or service available to a privileged group?
I don't know anyone who wants to push out "lower class" people. I do know lots of people who want to live in a San Francisco where everyone can afford rent. Everyone includes programmers, teachers, social workers, and dishwashers.
The professions you mentioned are government positions, which are largely funded with tax dollars. As it is, governments are currently full of people who are extremely anti-tax, and are against paying these people more.
The same was launched and failed in the same place (Toronto) in the year 2000, with locations at Go and Subway stations. I think Google will want to change the business model radically in some way.
Seriously, a Phd thesis not far from now may have the title: "The limits of AI: how far can we exploit the machines before we are limited by machine rights"
Actually, that is not just a thesis at some point in the future, that is an active field of study and has been since the 1980's. Some keywords are "machine ethics" and "AI rights". One of my friends wrote his PhD (in the 'real' sense, i.e. from a philosophy department - just to say that this is not (only) a CS topic) thesis about a question related to this in the early 80's.
A debugger loses much of its value in a functional language. Debugging Haskell or functional Scala code with a visual debugger is almost counterproductive.
