246 What's the smallest change to physics required to allow magic? 2016-04-29T10:18:21.727

129 What could people notice about someone who is two times as dense as a regular person? 2018-06-09T20:44:39.247

106 What would make scientists realize they were on a flat world? 2016-05-27T13:02:38.770

103 Would planets be cubic in my "cuboverse"? 2018-08-22T12:44:24.503

101 If our universe was a simulation, what could a bug look like? 2014-10-26T13:32:11.063

87 0g pool: can I keep a big ball of water in space? 2016-09-08T15:07:53.790

83 Would a 'World Tree' be feasible in real life? 2016-07-25T12:33:36.453

72 How to harness Jupiter's gravitational energy? 2016-11-02T14:58:14.213

71 How can powerful telekinesis avoid violating Newton's 3rd Law? 2019-06-08T20:47:50.223

70 How can you possibly stop/kill a person who has the ability to stop time? 2016-09-21T07:17:53.453

68 Plausible Reasons for usage of Combat Mecha 2015-02-16T03:01:44.780

68 Mineral that explodes when cooling down 2017-05-02T18:34:21.293

62 How can I get my DeLorean to 88 miles per hour without a train? 2015-10-23T01:19:48.363

59 If reality were frame-rate based, how could we detect it? 2018-10-15T14:51:40.573

58 What would it feel like on the surface of a planet while it collides with another planet? 2016-04-18T14:28:23.447

57 An infinite train circling the planet that never stops 2017-03-13T16:52:52.607

56 How soon can the first stars form? 2019-05-01T14:10:07.683

55 How fast would a sword need to be to avoid getting blood on it? 2017-04-09T03:56:03.433

51 If a large space ship crashes on a planet, what could kill passengers without obliterating the ship? 2018-07-26T16:35:40.887

50 Could two planets be tidally locked to each other so close they share their atmosphere? 2014-11-23T18:33:07.017

50 Could you have more than one building in the same spot by "stacking" them in 4th dimensional space? 2017-07-17T05:45:58.173

49 Can I use a trebuchet to launch satellites into space from a lunar colony? 2018-05-03T05:31:29.087

48 How would you know your floating island was losing altitude? 2018-02-15T14:17:40.940

48 Pressure inside an infinite ocean? 2019-04-30T16:38:37.467

47 What would be best way to re-melt Mars' mantle and core to revive its magnetosphere 2015-01-16T17:43:16.570

47 What if the speed of light were 100 times higher? 2015-02-12T02:26:32.280

47 Let’s say a 1 ton (US) sphere of tungsten moving at 99.99% the speed of light hits earth, what happens? As specific as possible 2018-12-04T07:24:43.883

46 What happens if the sun disappears and then reappears some days later? 2014-10-15T13:27:00.190

45 How many people would have to be killed to make the streets 'run red with blood'? 2017-04-19T20:17:36.810

45 What would happen if the Earth struck a tiny but immovable object 2018-05-23T13:17:55.513

44 Wondering what would happen if magic was constrained by Conservation of Energy 2014-09-25T00:57:07.180

44 Is there a scientifically valid explanation for a circle of islands? 2017-06-28T08:20:26.410

43 What would the periodic table of a 4-Dimensional universe look like? 2015-03-26T23:44:50.543

43 Would a horse be sufficient buffer to prevent injury when falling from a great height? 2019-09-24T02:44:15.510

42 How to prove that the solar system isn't inside of a localized physics bubble? 2017-03-13T23:35:32.193

41 Is there a scientifically sound faster-than-light travel system for a spaceship? 2014-09-21T08:48:22.837

40 Is there a working law of gravity in 2D? 2016-03-03T14:01:35.927

40 Only Three Books: Restarting Physics after civilization collapses 2018-01-10T00:49:54.877

37 Can I keep our universe, but without the speed limit (of light)? 2014-11-05T07:50:33.890

37 How, if at all, can space battleships mitigate gun recoil? 2016-04-22T08:48:23.227

37 Could a really fast man catch a bullet? 2018-09-04T20:09:03.783

37 Is it possible to encode a message in such a way that can only be read by someone or something capable of seeing into the very near future? 2019-09-19T02:11:27.310

36 What are the effects of slicing the Earth in half with a particle beam? 2018-07-13T19:01:19.113

36 What would be the effect of a giant magical fireball burning in the ocean? 2019-10-09T02:37:50.927

35 Precision Destruction by a Cosmic Being (Or how to destroy StackExchange from space) 2014-10-30T11:56:04.563

35 Is there a liquid that could protect a human inside it from impact? 2018-04-16T20:23:48.677

35 How do ballistic trajectories work in a rotating cylinder world? 2019-07-05T05:09:42.623

34 What would an efficient swimming creature in magma be like? 2017-06-24T08:29:57.827

34 How to create an annual celestial event for a world 2018-02-21T16:43:14.163

34 The Heisenberg Uncertainty Ray - A Hyper-Scanning Doomsday Weapon 2018-12-02T07:51:56.030

34 Lighthouse Alternatives 2019-09-25T11:45:45.800

33 How big would a pair of wings need to be to allow an adult human to fly in a given environment? 2014-10-20T12:42:59.690

33 Why isn't my superhuman always hungry? 2018-10-30T16:27:02.790

33 How to tell that you are a giant? 2019-04-16T08:42:35.323

33 How many pillows would you need to survive a fall from a church tower? 2020-01-06T18:56:43.713

32 How realistic is a dirty bomb for area-denial? 2017-10-11T14:23:06.447

31 What would happen if magic was constrained by the second law of thermodynamics 2014-10-05T05:40:45.253

31 What software can prototype a planetary system? 2014-10-09T11:20:15.927

31 How can it be bigger on the inside 2016-12-01T19:15:54.133

31 A planet rotating twice per second; what mass is needed to hold it together, and how oblate would it be? 2017-01-17T17:03:58.260

31 Could a WWI biplane fly if it were dropped from a high altitude instead of using a runway? 2017-08-11T04:46:55.237

31 How to detect that the universe got mirrored? 2019-01-08T10:07:44.217

31 A medieval fantasy adventurer lights a torch in a 100% pure oxygen room. What happens? 2019-09-09T17:23:59.777

30 Is there a scientifically plausible faster-than-light communication system? 2014-09-23T14:01:39.267

30 Would pyrokinesis be an effective defense? 2017-07-27T02:10:41.517

30 Lopsided artificial gravity 2017-12-11T17:24:34.960

30 How could indestructible materials be used in power generation? 2019-04-02T18:59:25.197

29 Star Matter Gate Blast Radius 2017-02-15T13:38:44.773

29 Could a human survive 5Gs for about two days using existing or near future technology? 2017-03-15T02:51:28.823

29 Is my plasma cannon concept viable? 2019-05-21T17:08:01.830

29 Can two moons have intersecting orbits yet be guaranteed not to collide? 2019-12-04T18:28:30.207

28 Explaining uphill rivers scientifically? 2015-03-07T21:17:29.930

28 Does it make sense for these space ships to have turrets? 2016-11-01T14:57:08.283

28 How high can Ludicrous Leg man jump? 2017-12-08T12:34:41.890

28 How many seconds would it take for my 20,000 ton kaiju to come to a complete stop from 15 or 30 mph? 2018-04-21T16:22:56.330

27 How can I estimate how far into a cave network breathing is possible? 2014-09-23T00:40:09.673

27 Feasibility of anti-matter as a fuel 2014-09-29T19:36:26.533

27 How might telekinesis and pyrokinesis work if they were possible? 2016-07-08T00:46:43.343

27 What would the effect be on Earth if Mars disappeared? 2016-08-03T08:56:53.990

27 Sailing without wind, but with strong currents 2018-06-14T07:43:26.907

27 Would one atom of antimatter be lethal if annihilated inside the brain? 2018-11-30T07:29:05.857

26 Encasing a star in a perfect insulator 2016-11-11T16:59:02.380

26 Can wind immediately freeze something? 2017-02-09T19:05:10.767

26 How could a submarine-like vehicle steer and propel itself in a superfluid? 2017-02-09T23:06:19.767

26 What happens when a moving vehicle loses all its kinetic energy at once 2018-07-05T03:12:25.680

25 What could cause rock formations (small stones, boulders, islands...) to levitate? 2014-09-17T07:19:14.643

25 Plausible plasma weapons? 2014-10-30T12:32:17.523

25 What would birds look like if they used buoyancy to fight gravity? 2019-01-18T16:18:19.897

25 Could a 19.25mm revolver actually exist? 2019-05-23T14:01:43.580

25 Moonlight bright enough to see by 2019-10-09T15:33:53.450

24 How would the human body develop under a different gravity? 2014-11-07T14:42:44.510

24 How might one explain (pseudo-scientifically) the generation of a "projected," guided darkness? 2014-11-18T21:04:58.043

24 What are some plausible super materials? 2015-11-15T03:54:06.453

24 How to safely derail a train during transit? 2019-03-27T09:23:18.547

24 Justifying the use of directed energy weapons 2019-08-21T08:51:37.633

23 Is it possible to advertise on the moon? 2014-10-02T14:19:39.633

23 How deep underwater do I have to dive to be safe from a 1MT Hydrogen bomb detonation above? 2016-02-09T19:46:45.420

23 What colour is the foliage if the sky is violet? 2016-12-03T16:27:44.973

23 Can you replace a sun with a burning moon? 2017-04-28T17:17:43.373