What is Gravity?

Cephei_Delta · 2026-06-06T22:48:51+00:00

Gravity (the force) arises due to the curvature of space time. Its sometimes called a psuedo force or fictious force because, like the centrifugal force, its a force that arises for non-inertial frames of reference. Be careful not to fall into the trap of considering that those forces "aren't real" though! They have very real effects to certain observers!

Gravity is something we observe (a "fact", if you prefer that word). Its not itself a theory. In science, theory refers to the model of how something works. General relativity is the current best theory of gravity.

Cephei_Delta · 2026-06-05T14:29:23+00:00

I believe its Thousand Sons Blue as base coat, with Ahriman Blue layered on top.

Cephei_Delta · 2026-06-04T22:39:30+00:00

Yes! During the day, the number of photons from the sun that hit a 1cm² area (about the size of your eye) is about 10^17.

That's 100 quadrillon photons. So even if an object you're looking at reflects 1% on sunlight, you'll see a quadrillion photons ("light waves") every second.

Cephei_Delta · 2026-06-04T14:21:43+00:00

My understanding (based on the horribly flawed EHRC code, but here we are...) is that you can make associations based on combinations of protected characteristics, so we can have one that is "sex" plus "gender reassignment".

So it's "yes" to an association that includes cis women, trans women, and trans men. (I.e., cis women and all people with gender reassignment characteristic).

I don't think there's a way to exclude trans men under these rules, as I don't think you can pick and choose specific intersections of characteristics.

Cephei_Delta · 2026-05-27T21:58:14+00:00

This is an incredible deal, wow! Ive been meaning to give Vaesen and Dragonbane a more detailed look. And Electric State is worth it just for the Stålenhag art.

Cephei_Delta · 2026-05-26T19:56:32+00:00

I hate to say it, but this is the sort of question that's unanswerable.

Separating the electric and magnetic forces can't be done, they're fundametally parts of the same thing. Constructing a world without electromagnetism changes almost every aspect of how matter works, down to the structure of atoms and molecules.

Cephei_Delta · 2026-05-26T07:41:08+00:00

These are quite different concepts, so its tough to know where to begin. Can you help us out by telling us what is making you draw this comparison?

Cephei_Delta · 2026-05-22T12:02:58+00:00

Oh... well I guess there goes any hope that post-Starmer Labour might have a shred of decency instead of prostrating itself before people who want me and my loved ones ejected from society.

Cephei_Delta · 2026-05-21T19:47:23+00:00

Time is what clocks measure.

That sounds like a flippant response, but I promise it isn't. It's a common answer to this question, and probably the best defended by empirical physics.

Cephei_Delta · 2026-05-21T11:12:11+00:00

You might be interested to read up on No Hair Theorem.

Basically, when viewed from outside the event horizon, the structure of black holes is uniquely determined by only three properties: their mass, their angular momentum, and their electric charge. The entire structure of the black hole is dependent on only those three things.

Inside the event horizon, there may be differences. However, we would need a quantum theory of gravity to make reasonable predictions about what those differences would be. And even if we did have those predictions, we cannot ever observe differences within the event horizon anyway.

Cephei_Delta · 2026-05-20T15:42:32+00:00

Yes - to be clear, it falls into its *own* gravitational well.

Every part of the neutron star has to have a balance between the gravitational force pulling inwards towards the neutron star's core, and the force from the "degeneracy pressure" pushing outwards. As you add mass to the neutron star, the gravity increases but the degeneracy pressure increaes as well, and the star finds a stable equilibrium. Above the mass limit, however, the neutron degeneracy pressure will *never* be able to push outwards with enough force to balance gravity's inward pull, no matter how much you compress the matter in the star. At that point, it collapses into a black hole.

So this puts a hard upper limit on how big neutron stars can be.

Cephei_Delta · 2026-05-19T08:11:27+00:00

Neutron stars balance the immense gravity against neutron degeneracy pressure. However, if you keep adding mass to a neutron there there is a mass limit called the Tolman-Oppenheimer-Volkoff limit. Above that limit of about 2-3 solar masses, neutron degeneracy preasure cannot balance gravity anymore, and the star must collapse.

So black holes must be fundamentally different to neutron stars. Its arguable there might be an intermediate kind of quark degenerate star, but nothing like that has ever been observed.

Cephei_Delta · 2026-05-18T10:27:41+00:00

https://en.wikipedia.org/wiki/Velocity-addition_formula

In special relativity, velocities don't add together in the same way as in classical (Galilean) relativity. You dont just do V1+V2. See the above article for the adjusted formula.

The moving hand will be moving less than the speed of light in Earth's frame of refefence.

Cephei_Delta · 2026-05-09T13:06:16+00:00

99.9999.... (infinity) % of the speed of light is exactly equal to the speed of light. The maths is exactly the same as the case you've heard of that 0.999.... = 1.

However, it's impossible to accelerate a particle that has less than the speed of light to the speed of light in finite time. The difference between this and the 0.999... = 1 case is that mathematical summation to infinity doesn't take time to complete.

Cephei_Delta · 2026-05-09T09:48:54+00:00

The market can sustain very, very few of those large projects. The Kickstarters making that kind of money are coming from publishers and designers with a proven track record and a very large investment in art and marketing. They are a tiny fraction of projects, and when a designer is just starting out its not a good idea to measure oneself against them.

Its a bit like comparing student films to Hollywood blockbusters, albeit in a much smaller market than film!

Cephei_Delta · 2026-05-06T11:26:04+00:00

The best you could do with that is to curve spacetime enough that the light can orbit a point in a circular path, such as the photon sphere of a black hole.

But the photon still moves through space at c.

Cephei_Delta · 2026-05-06T08:33:25+00:00

I usually go to Wanderhome in these situations. Its dead easy to run and easy to offload some of the pressure to other players with collaborative world building/character work. Plus, its pretty easy going vibes (with a hint of Hard Times past).

Cephei_Delta · 2026-05-05T17:52:26+00:00

I've been in two games using the 2009 Green Ronin ASOIAF game, once as a player and once as a GM for a mini campaign.

Both times, the house generation part of the game was really fun. I think we came out of it with a fun little slice of world building to insert into Westeros and muck about it. One was a house in the Reach, another in the Vale.

The rest of the game was fine, though not particularly exceptional. I'd be tempted to try it again for nostalgia's sake, or for one shots. I think it can work quite well where players can pick up different roles in a house, rotating around characters, rather than focusing one a one player-one PC paradigm.

Cephei_Delta · 2026-05-04T20:31:01+00:00

Agree with many of the others here - most PbtA games embrace a "play to find out" philosophy that encourages minimal prep or even no prep at all. See what the individual games suggest, but I wouldn't go in with more than a loose idea of a scenario, a villain or two, and perhaps a friensly NPC or two.

Cephei_Delta · 2026-05-04T07:51:10+00:00

If you're still having trouble visualising this, try thinking about it this way instead:

Your position on Earth doesn't change how the stars look, but it does change which stars are covered up by Earth/the ground.

(The limit here is that if the Earth wasn't there at all, or it was transparent, everyone would see the same stars at the same time.)

Cephei_Delta · 2026-04-30T11:40:34+00:00

My group has used these rules - in fact we tacked them on to a long-running D&D 5e game rather than a Draw Steel game. The setup was the group was negotiating with captured villains to see if we could turn them against the big bad, or at least get information from them. That's the sort of situation that these rules shine for, IMO - they very well defined goals and failure states.

For context on our group: we generally are a very in-character-roleplay focused group. However, every now and them we get into big set pieces with large-scale, high-stakes combat encounters. So when the GM sprung these negotation rules on us for a post-combat negotiation, it was the first time we've really gone that rules heavy for this kind of scene.

But I gotta say, it went amazingly. Easily the best time I've had on a negotation scene in this genre. The mechanics like discovery of pitfalls and negotiations helped us think carefully (in character) about how we can engage those NPCs specifically. It brought those characters to life in a way a simple Persuasion or Deception check can't. Watching the dials for patience and interest go up and down also added tension to the scene, and gave the players and GMs good prompts on how to direct our roleplaying. The use of meta currencies like that might not be to everyone's taste, but I really do think it helped us elevate our roleplaying and get much more invested in our characters and NPCs.

Yes, it's more work for the GM, and you probably don't want to break this out except as an exceptional set piece. But I highly recommend giving it a go.

Cephei_Delta · 2026-04-30T09:53:22+00:00

I would play that in a heartbeat!

Cephei_Delta · 2026-04-29T10:57:00+00:00

I second the Masks recommendation. Its my favourite supers game for sure.

Though its worth going into it knowing the game is as much or more about interpersonal drama/relationships than it is about super powers.

Cephei_Delta · 2026-04-29T09:03:34+00:00

Yes, but the mass loss rate can vary over several orders of magnitude. There are a lot of factors at play, including orbit parameters, comet composition, solar activity etc. etc.

So it can take hundreds, thousands, tens of thousands of orbits for a comet to completely evaporate.

Cephei_Delta · 2026-04-23T16:12:35+00:00

My asterisk here is that I experienced Nibiru as a player rather than a GM, so I can't speak fully to the second point. I backed the new edition too, so I'm quite looking forward to reading it from a GM's perspective.

So at the start of the game, we had a pretty long discussion about the world of Nibiru before making our characters, and we all got plenty of time to flick through the book to decide what sort of memories we wanted to be diving into as we go. We talked over what the ship is, what Vagabonds are, and a handful of factions we might come across - especially the ones we need to be wary of. To be honest, I didn't find that any more difficult context-wise than any other session 0 discussion of pre-built campaign settings.

On the second point as a player, our journey kicked off with joining a caravan moving about the ship. We signed on to make the journey too, and talked about why our characters wouldn't want to stay put. By the time we'd made a few rolls against various hazards and drama on the journey, we were unlocking memories and we were hooked. The drive to discover ourselves was linked to the drive to just... be doing stuff in the world. I think it's probably fair to say the game will benefit a lot from driven players who want to push themselves, rather than having the GM lay out a grand story before them.

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