WEBVTT 1 00:00:00.200 --> 00:00:02.120 Hi there, thanks for joining us. This is a Q 2 00:00:02.279 --> 00:00:06.320 and a edition of Space Nuts. My name is Andrew Dunty. 3 00:00:06.799 --> 00:00:09.759 Coming up, we're going to look at a lot of issues, 4 00:00:09.800 --> 00:00:15.720 one involving dark matter. This question, though, comes about as 5 00:00:15.720 --> 00:00:19.239 a consequence of someone who wasn't real happy with a 6 00:00:20.199 --> 00:00:25.679 discussion we had recently, so we'll we'll certainly reinvestigate that. 7 00:00:26.440 --> 00:00:29.640 We'll also look at flawed mathematics. That sounds like my 8 00:00:29.839 --> 00:00:33.679 entire school career. We'll also be discussing black holes and 9 00:00:33.719 --> 00:00:36.880 gravity and energy in space. That's all coming up on 10 00:00:36.920 --> 00:00:41.359 this edition of Space Nuts fifteen seconds. Guidance is in 11 00:00:41.479 --> 00:00:49.000 channel ten nine ignition sequence Space Nuts or three. 12 00:00:49.119 --> 00:00:51.679 Two more review on. 13 00:00:52.039 --> 00:00:56.359 Space Nurse as can I reported Bills good and joining 14 00:00:56.399 --> 00:00:59.280 us again to sort all of this out is Professor 15 00:00:59.280 --> 00:00:59.920 Fred Watson. 16 00:01:00.200 --> 00:01:05.560 Hello Fred, Hello, I do let's get into those questions? Eh, Yes, 17 00:01:06.840 --> 00:01:09.120 let's just hit the nail on the head and start. 18 00:01:09.359 --> 00:01:13.359 And this first question comes about as a consequence of 19 00:01:13.439 --> 00:01:18.359 us answering a previous question. And I think we've kind 20 00:01:18.359 --> 00:01:21.760 of put Kevin's nose out of joint just slightly, I 21 00:01:21.920 --> 00:01:25.840 might say, though he's used a word that I think 22 00:01:25.959 --> 00:01:30.040 is probably not in keeping with the way you deal 23 00:01:30.120 --> 00:01:33.200 with things spread, I would never ever accuse you of 24 00:01:33.239 --> 00:01:38.079 being glip. However, that said, Kevin does have issue with 25 00:01:38.519 --> 00:01:42.359 the dark matter question. Now, so that I don't mash 26 00:01:42.480 --> 00:01:47.560 Kevin's question up, I have prepared it with an AI 27 00:01:47.760 --> 00:01:50.079 voice so that it comes out clean and. 28 00:01:51.359 --> 00:01:55.400 Unadulterated, if you like. So, let's see what the issue 29 00:01:55.439 --> 00:01:58.719 is and see if we can pick at the pieces 30 00:01:58.719 --> 00:02:02.840 and put it back together again. This is from Kevin. 31 00:02:02.640 --> 00:02:04.840 In your four hundred and twenty eighth episode. I was 32 00:02:04.879 --> 00:02:07.359 saddened by your response to a listener question asking if 33 00:02:07.400 --> 00:02:10.400 space time itself might be dark matter. I found your 34 00:02:10.439 --> 00:02:13.240 emphatic and almost glib No. Just doesn't fit with your 35 00:02:13.240 --> 00:02:17.000 regular open mindedness. I have asked similar questions before in 36 00:02:17.080 --> 00:02:20.479 other forums and received the same dismissive no response without 37 00:02:20.479 --> 00:02:23.560 any depth of thinking about the question. For starters, we 38 00:02:23.599 --> 00:02:26.400 don't yet know what space time actually is, but if 39 00:02:26.439 --> 00:02:28.479 it can be distorted, it has some aspect of a 40 00:02:28.520 --> 00:02:31.400 substance to it, and if it is a form of substance, 41 00:02:31.479 --> 00:02:33.439 why should it not be considered as a candidate for 42 00:02:33.520 --> 00:02:37.199 dark matter. It is everywhere, it is transparent to em 43 00:02:37.240 --> 00:02:40.199 it is weakly interacting it can be distorted, which means 44 00:02:40.240 --> 00:02:43.080 what that it becomes more dense in some areas than others. 45 00:02:43.439 --> 00:02:45.560 So what if areas that are denser have a positive 46 00:02:45.599 --> 00:02:50.159 gravitational effect compared to average background space, you might see clumping. 47 00:02:50.360 --> 00:02:52.199 So what if areas that are less dense have a 48 00:02:52.240 --> 00:02:55.639 repulsive gravitational effect compared to average background. 49 00:02:55.159 --> 00:02:57.319 Space, you might see voids. 50 00:02:57.520 --> 00:03:00.000 I'm not saying space time is dark matter, but dark 51 00:03:00.080 --> 00:03:02.479 matter is not actually a thing that has been discovered yet. 52 00:03:03.159 --> 00:03:05.800 Variable density space time maybe all that is needed to 53 00:03:05.840 --> 00:03:08.639 explain the gravitation anomalies that we observed, and I think 54 00:03:08.639 --> 00:03:11.039 it deserves a more open minded level of exploring than 55 00:03:11.080 --> 00:03:13.639 a simple dismissal. What I'd like to know is how 56 00:03:13.639 --> 00:03:17.199 would you test it as hypothesis? Has anyone done said testing? 57 00:03:17.520 --> 00:03:20.560 Has it been exhaustively ruled out by whom? How did 58 00:03:20.560 --> 00:03:24.039 they do that? Otherwise? Brilliant show. Kevin from Melbourne. 59 00:03:24.680 --> 00:03:26.840 Okay, Kevin, thank you very much. I hope you don't 60 00:03:26.840 --> 00:03:31.039 mind me using AI to put that question out there. 61 00:03:31.080 --> 00:03:34.599 I just wanted to make sure it was intact, because 62 00:03:37.400 --> 00:03:41.240 you obviously are very serious about this issue, and you 63 00:03:42.560 --> 00:03:45.599 have had problems in the past getting a straight answer, 64 00:03:45.879 --> 00:03:48.639 and you put a lot of thought into it. I 65 00:03:48.719 --> 00:03:53.319 give you credit for that. So, Fred, how can we 66 00:03:54.080 --> 00:03:59.240 sort of discuss this question with a more robust approach. 67 00:04:00.199 --> 00:04:03.719 By getting somebody who's more of a specialist in dark 68 00:04:03.759 --> 00:04:11.639 matter physics and cosmology than me as as a commentator. 69 00:04:11.879 --> 00:04:14.680 I mean, what I report on is what I understand 70 00:04:14.719 --> 00:04:17.959 from the work of my colleagues who work in this 71 00:04:18.079 --> 00:04:23.959 sort of field. And there's certainly nothing I've heard and 72 00:04:24.040 --> 00:04:29.560 seen in the literature that would equate dark matter with 73 00:04:29.680 --> 00:04:35.560 space time. It is always regarded as something that exists 74 00:04:35.600 --> 00:04:39.680 within space time. Now there'll be there'll be very good 75 00:04:39.720 --> 00:04:46.519 reasons for that, and almost certainly if some of my 76 00:04:46.639 --> 00:04:50.079 friends and colleagues were sitting right here now, they would 77 00:04:50.120 --> 00:04:53.000 be able to point us in the right direction as 78 00:04:53.040 --> 00:04:55.600 to why that is the case. I haven't checked the 79 00:04:55.639 --> 00:05:01.560 details myself, but nobody is making that such. Yes, it is. 80 00:05:02.759 --> 00:05:08.600 It's almost universally accepted as being a sub atomic particle 81 00:05:08.600 --> 00:05:12.560 of some kind which exists within space time that we 82 00:05:12.600 --> 00:05:17.720 haven't yet detected. I'm sorry if I sounded glid, but 83 00:05:17.759 --> 00:05:21.560 it wasn't. Certainly wouldn't have been my intention, and dismissive. 84 00:05:21.680 --> 00:05:26.480 Isn't something I like to be described as either because 85 00:05:26.839 --> 00:05:30.920 you know, we normally, we normally exactly keep an open 86 00:05:30.920 --> 00:05:33.120 mind about many of these issues. And part of that 87 00:05:33.199 --> 00:05:36.759 open mindedness is because I'm not a specialist in the field. 88 00:05:36.839 --> 00:05:40.920 I'm reporting on what, you know, what my colleagues, not 89 00:05:41.079 --> 00:05:44.959 just one of them, but many of them are saying, so, yeah, 90 00:05:45.040 --> 00:05:49.160 let's keep it, keep it in mind. I will explore 91 00:05:49.199 --> 00:05:51.560 it a little bit further, the idea that Jody's going 92 00:05:51.600 --> 00:05:57.160 to get involved as well. I'll explore the reasons why 93 00:05:57.800 --> 00:06:01.879 we don't consider it to be part of space until 94 00:06:01.959 --> 00:06:02.480 later date. 95 00:06:03.160 --> 00:06:04.519 Okay, No, that's fair enough. 96 00:06:04.600 --> 00:06:06.560 I mean, thanks for your comments. 97 00:06:06.920 --> 00:06:11.399 Yeah, and look, I appreciate his frustration because he's obviously 98 00:06:11.439 --> 00:06:14.240 tried to get answers on this and may not have 99 00:06:14.439 --> 00:06:17.839 liked the way we approached it at that particular time. 100 00:06:17.959 --> 00:06:22.920 But it is an area that is under heavy investigation. 101 00:06:23.600 --> 00:06:26.920 Everyone is looking at. Even one or two episodes ago, 102 00:06:27.000 --> 00:06:31.519 we talked about a particular search for dark matter that 103 00:06:31.600 --> 00:06:35.800 came up with nothing, And that doesn't mean it doesn't exist. 104 00:06:35.920 --> 00:06:38.759 In fact, we know it exists. They just haven't found 105 00:06:38.800 --> 00:06:42.480 it within certain parameters, and so they'll be looking bigger. 106 00:06:42.519 --> 00:06:46.920 But that particular equipment hasn't actually been built yet, so 107 00:06:47.920 --> 00:06:54.360 the frustration continues. So we hopefully are not a long 108 00:06:54.399 --> 00:06:59.480 way off figuring out dark matter. But right now there's 109 00:06:59.680 --> 00:07:04.319 lots small questions than there are answers, and it's I 110 00:07:04.360 --> 00:07:08.680 supposed to watch this space scenario, but no. We appreciate 111 00:07:08.720 --> 00:07:12.439 you passing on your thoughts, Kevin, and hopefully we will 112 00:07:12.480 --> 00:07:16.160 be able to come up with some more information moving 113 00:07:16.199 --> 00:07:20.720 forward once we've looked into it through the respective experts. 114 00:07:22.639 --> 00:07:24.920 Let's move on to our next question. This comes from 115 00:07:25.319 --> 00:07:29.519 Simon and he says, hi, is it possible that the 116 00:07:29.560 --> 00:07:32.959 breakdown of models at extremes of the universe is due 117 00:07:33.000 --> 00:07:37.439 to our mathematics being flawed rather than the models? For example, 118 00:07:37.839 --> 00:07:44.000 fluid dynamic models of real world scenarios rely on imaginary numbers. 119 00:07:44.319 --> 00:07:48.360 Might our system of mathematics be slightly misaligned with the 120 00:07:48.399 --> 00:07:53.000 real world? Thank you, Simon. I think we've kind of 121 00:07:53.040 --> 00:07:57.240 talked about the mathematics being off in respect to some 122 00:07:57.360 --> 00:08:01.040 things in the past, and even Einstein consider is the 123 00:08:01.360 --> 00:08:05.600 model of relativity is probably not right, even though we 124 00:08:05.600 --> 00:08:08.759 can't prove it wrong. So it is a good question 125 00:08:08.839 --> 00:08:12.079 to ask, and the answer is yeah, probably somewhere along 126 00:08:12.079 --> 00:08:14.000 the line, then the numbers don't stack up. 127 00:08:15.079 --> 00:08:19.399 Yeah. I think it's an interesting you know Simon's postulate 128 00:08:19.439 --> 00:08:26.319 about particularly about imaginary numbers, which is we call them 129 00:08:26.360 --> 00:08:30.240 complex numbers. They have a real and an imaginary component. 130 00:08:30.879 --> 00:08:33.159 Why is it imaginary because it's the square root of 131 00:08:33.200 --> 00:08:40.799 minus one, which doesn't exist. But it's an incredibly useful 132 00:08:40.840 --> 00:08:45.559 tool in so many fields of science and engineering too. 133 00:08:46.320 --> 00:08:50.399 Your aerodynamics relies on the imaginary numbers, so it's imaginary 134 00:08:50.519 --> 00:08:54.919 numbers that keep you plane in the air. Could could 135 00:08:55.000 --> 00:08:58.840 that understanding be flawed? Yes? I think it could. And 136 00:08:58.919 --> 00:09:01.840 again I think, you know, we are pretty open minded 137 00:09:01.879 --> 00:09:10.639 about this idea. What breaks down our physics in the 138 00:09:10.720 --> 00:09:13.879 extreme situations that I think Simon's referring to things like, 139 00:09:14.480 --> 00:09:17.960 you know, how do you deal with the way the 140 00:09:18.080 --> 00:09:21.799 universe behaved immediately after the Big Bang, where you've got 141 00:09:21.879 --> 00:09:25.919 temperatures and pressures that we've got no physical experience of 142 00:09:26.759 --> 00:09:30.600 in terms of working out how they would behave, and 143 00:09:30.639 --> 00:09:33.879 they become what we call highly nonlinear. That means that 144 00:09:33.919 --> 00:09:37.000 they behave in a way that is actually really hard 145 00:09:37.000 --> 00:09:42.360 to predict. And so that's saying that our physical models 146 00:09:42.639 --> 00:09:47.759 are not are not robust enough, not necessarily that the 147 00:09:47.799 --> 00:09:52.320 mathematics is not robust enough, but it is an interesting conjecture. 148 00:09:54.039 --> 00:09:59.279 I yeah, I think Simon's point is well made. Might 149 00:09:59.320 --> 00:10:01.960 our system of mathematics be slightly misaligned with the right 150 00:10:02.039 --> 00:10:04.639 real world? Well, in extreme cases it probably is. When 151 00:10:04.679 --> 00:10:08.000 you think about, you know, the temperature immediately after the 152 00:10:08.039 --> 00:10:08.519 Big Bang. 153 00:10:09.480 --> 00:10:13.840 Well, yeah, that's a good point. I mean it's no 154 00:10:13.960 --> 00:10:18.320 easy remedy though, is this? No? 155 00:10:19.240 --> 00:10:24.480 I mean there are people who are modeling those scenarios 156 00:10:24.519 --> 00:10:27.039 where you do have these extremes, and they're probably relying 157 00:10:27.080 --> 00:10:31.759 on relatively conventional mathematics, although yes, the other they will 158 00:10:31.799 --> 00:10:34.840 involve complex numbers and all the rest of it. But 159 00:10:34.960 --> 00:10:39.399 I yeah, I think it gets weirdest. Actually, it gets 160 00:10:39.440 --> 00:10:46.000 weirder in the quantum world, where we've got all kinds 161 00:10:46.039 --> 00:10:52.480 of interesting notions that do rely heavily on mathematics, superposition, entanglement, 162 00:10:52.559 --> 00:10:56.519 all of these things, and they rely on particular types 163 00:10:56.559 --> 00:11:00.159 of mathematics Hilbert spaces and things of that sort, which 164 00:11:00.200 --> 00:11:05.840 are well understood. I have to say, but to you know, 165 00:11:05.960 --> 00:11:10.480 to the uneducated, and I include myself in that, because 166 00:11:10.519 --> 00:11:15.240 mathematics was my achilles heel at university nearly cost me 167 00:11:15.320 --> 00:11:21.399 my degree. The I think they look these things look 168 00:11:21.559 --> 00:11:24.039 like mathematics gone wrong, if I can put it that way, 169 00:11:24.080 --> 00:11:28.440 but they haven't. They we'll understood. So the misalignment with 170 00:11:28.519 --> 00:11:34.000 the real world, I think it's possible. But in many ways, 171 00:11:34.039 --> 00:11:36.320 the mathematics is all we've got to rely on, so 172 00:11:36.360 --> 00:11:38.360 we just keep plodding on with what we know. 173 00:11:38.840 --> 00:11:42.519 Yeah, you mentioned superposition. I've just finished watching a science 174 00:11:42.519 --> 00:11:49.000 fiction series called Dark Matter, right, and they the goal 175 00:11:49.279 --> 00:11:54.519 of the main character, the scientist, that was the whole 176 00:11:54.519 --> 00:11:59.440 story was built around. His aim was to achieve superposition 177 00:11:59.720 --> 00:12:06.080 so they could travel into dimensionally. It was brilliantly done. 178 00:12:06.240 --> 00:12:11.080 Brilliantly done. They obviously had to work out how to 179 00:12:11.159 --> 00:12:14.919 make it a convincing storyline for those who are so 180 00:12:15.399 --> 00:12:19.279 into science fiction and science for that matter, to make 181 00:12:19.320 --> 00:12:22.000 it plausible, and they did a great job. It's a 182 00:12:22.120 --> 00:12:27.840 brilliant story, brilliant series. Really enjoyed it. Won't spoil it 183 00:12:27.879 --> 00:12:30.480 by telling you how it ended, but I doubt there 184 00:12:30.480 --> 00:12:33.360 will be a sequel because it did end, and it 185 00:12:33.399 --> 00:12:37.399 did end well. I thought, Okay, was it cool to 186 00:12:38.000 --> 00:12:41.759 dark Matter? Dark Dark Matter? And I think it was 187 00:12:41.799 --> 00:12:46.399 on Netflix. I can't remember now, But yeah, terrific series. 188 00:12:46.559 --> 00:12:49.919 Really enjoyed it and just so you know they could 189 00:12:49.919 --> 00:12:55.519 have well they did. It got so very confusingly complicated 190 00:12:55.919 --> 00:12:59.720 towards the end, but yeah, that's what made it so interesting. 191 00:13:01.120 --> 00:13:04.120 Thank you, Simon, And our next question coming up in 192 00:13:04.159 --> 00:13:08.039 a moment. 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Now back to the show. 223 00:15:10.240 --> 00:15:15.120 We're old on space Nuts and that's a moment this right, 224 00:15:15.919 --> 00:15:22.039 This one's from Isaac on the Gold. It is from Brisbane, 225 00:15:22.039 --> 00:15:26.559 actually in Australia. Isaac is nine years old. He said, 226 00:15:26.600 --> 00:15:30.679 I have two questions, how do black holes spin if 227 00:15:30.679 --> 00:15:35.200 they take up no space? And why does spin affect space? 228 00:15:37.200 --> 00:15:40.399 And his dad's got a question as well. My dad 229 00:15:40.440 --> 00:15:43.799 asks how does gravity bend space and thus bend light 230 00:15:44.000 --> 00:15:49.000 traveling past it? Isaac in Brisbane, nine years old. Great 231 00:15:49.000 --> 00:15:51.320 to hear from your Isaac. Thanks for sending your questions 232 00:15:51.320 --> 00:15:54.080 in why do black holes spin? I think someone else 233 00:15:54.120 --> 00:15:55.840 asked a similar question percently. 234 00:15:56.039 --> 00:15:58.919 We covered this not very long ago. Yeah, and so 235 00:15:59.120 --> 00:16:01.720 what you've got to think about is how black black 236 00:16:01.720 --> 00:16:07.000 holes are formed. If you have a star which is 237 00:16:07.120 --> 00:16:10.519 more than you know, ten times the mass of the Sun, 238 00:16:10.679 --> 00:16:14.320 something like that, gets to the end of its life, 239 00:16:13.799 --> 00:16:20.679 the nuclear propulsion system of the star stops until gravity 240 00:16:20.759 --> 00:16:26.320 takes over and the star collapses or its core collapses 241 00:16:27.000 --> 00:16:30.240 to become a black hole. So what you've got is 242 00:16:30.279 --> 00:16:33.240 a star that is going to be spinning. It will 243 00:16:33.440 --> 00:16:39.120 rotate because everything is rotating or evolving, and as it rotates, 244 00:16:39.679 --> 00:16:42.879 the spin will get faster because of the conservation of 245 00:16:42.879 --> 00:16:48.120 angular momentum. So spin is conserved. So even when the 246 00:16:48.320 --> 00:16:53.399 black hole becomes something that, as Isaac says, takes up 247 00:16:53.440 --> 00:16:58.480 no space, it's still spinning. Even though it is a 248 00:16:58.519 --> 00:17:02.879 single point. It's still spinning because it's the original style 249 00:17:02.919 --> 00:17:05.640 that collapsed to form. It was spinning, so that spin 250 00:17:05.759 --> 00:17:07.240 gets imparted to the black hole. 251 00:17:07.839 --> 00:17:09.640 So it's just inheriting basically. 252 00:17:10.039 --> 00:17:11.720 Yes, that's right. It's a good way of putting it, 253 00:17:11.799 --> 00:17:16.160 an inherited spin. I think I've got that as well. 254 00:17:16.880 --> 00:17:20.759 So and Isaac's dad wants to know how gravity bend space. 255 00:17:20.839 --> 00:17:25.880 We all want to know that actually, because it's what 256 00:17:25.920 --> 00:17:28.480 we know is how much in bend space. We do 257 00:17:28.599 --> 00:17:33.559 understand the mechanics of what happens when you put mass there. 258 00:17:33.599 --> 00:17:38.640 You can you can accurately predict just how and how 259 00:17:38.720 --> 00:17:44.480 much space will be bent, but why does it happens. 260 00:17:45.279 --> 00:17:49.119 It's the effect of gravity. That's the phenomenon we call gravity, 261 00:17:49.240 --> 00:17:52.400 and at that level we really don't understand it very well. 262 00:17:53.240 --> 00:17:55.720 Yeah, this is the thing. We know dark matter exists. 263 00:17:55.720 --> 00:17:59.079 We can't prove it yet. We know gravity exists, but 264 00:17:59.160 --> 00:18:03.240 we don't know about how it exists, in the way 265 00:18:03.279 --> 00:18:05.720 it exists, and whether or not it's a subatomic particle 266 00:18:05.759 --> 00:18:06.519 called a graviton. 267 00:18:08.279 --> 00:18:08.519 Yeah. 268 00:18:08.680 --> 00:18:10.680 I mean, we know a lot of things that exist, 269 00:18:10.759 --> 00:18:13.839 but we don't know much about why they exist and 270 00:18:13.880 --> 00:18:15.039 how they exist. 271 00:18:15.240 --> 00:18:17.960 Yeah, I suppose what you could say, is that we 272 00:18:18.039 --> 00:18:21.160 know extremely accurately. And this was you know, one of 273 00:18:21.200 --> 00:18:25.680 your answers to that last question. Relativity works like a dream. 274 00:18:25.799 --> 00:18:31.079 Everything is so precise, following the rules that Einstein laid 275 00:18:31.079 --> 00:18:37.519 out in nineteen fifteen. So that describes gravity incredibly well, 276 00:18:37.680 --> 00:18:41.720 incredibly accurately. But it is still only a description of gravity. 277 00:18:41.799 --> 00:18:46.160 It's not an understanding of how gravity arises. And so yes, 278 00:18:46.799 --> 00:18:48.480 we still have big mysteries. 279 00:18:48.039 --> 00:18:54.440 Though relatively speaking. Indeed, Yes, thanks Isaac, great to hear 280 00:18:54.480 --> 00:18:57.599 from you. Please send us questions again. I always love 281 00:18:57.640 --> 00:19:02.960 to hear from our younger listeners. And finally we have 282 00:19:03.480 --> 00:19:06.759 a question from our old mate Rusty. I believe Rusty 283 00:19:06.799 --> 00:19:07.680 is from Donnie Brook. 284 00:19:09.759 --> 00:19:13.680 Gooday, Fred and Andrew and all you space nuts. It's 285 00:19:13.759 --> 00:19:17.559 Rusty and Donny Roop, Western Australia. It seems to me 286 00:19:17.880 --> 00:19:23.920 that soon, and that may be in astronomical terms, we'll 287 00:19:23.960 --> 00:19:28.440 be able to harness the energy of space itself. We 288 00:19:28.519 --> 00:19:32.319 know there's a lot of energy in space. It has 289 00:19:32.359 --> 00:19:35.279 most of it if you look at the expanding universe 290 00:19:35.400 --> 00:19:41.720 and dark energy. But when we do harness the energy 291 00:19:41.920 --> 00:19:45.319 energy of space, we should be able to crank up 292 00:19:46.039 --> 00:19:50.839 one g drives and that allow us to go anywhere 293 00:19:50.880 --> 00:19:59.640 we like with swop over halfway, so the first half 294 00:19:59.680 --> 00:20:02.359 of the whege is accelerating at one g and the 295 00:20:02.400 --> 00:20:04.839 second half is decelerating at one G. 296 00:20:05.799 --> 00:20:06.839 A funny thing happens. 297 00:20:06.960 --> 00:20:07.599 The crew. 298 00:20:09.960 --> 00:20:13.519 To them seem to be traveling faster than the speed 299 00:20:13.559 --> 00:20:16.599 of light, so that they would go to Andromeda under 300 00:20:16.599 --> 00:20:19.799 these circumstances. 301 00:20:18.880 --> 00:20:21.079 In thirty crew years. 302 00:20:21.759 --> 00:20:26.480 So just wondering what Fred and Andrew, what your priorities 303 00:20:26.519 --> 00:20:29.839 would be once we do develop this drive both for 304 00:20:29.880 --> 00:20:31.000 the Solar System. 305 00:20:30.720 --> 00:20:35.400 And in the wider universe. Thank you, Oh Rusty, just 306 00:20:35.440 --> 00:20:40.359 put us right there in the middle of it. What 307 00:20:40.400 --> 00:20:44.640 would our priorities be over to you, Fred. 308 00:20:44.279 --> 00:20:48.880 Well, I've kind of said this before, and it's something 309 00:20:48.920 --> 00:20:53.880 that almost you know, rust is almost hinted by referring 310 00:20:53.880 --> 00:20:59.720 to a trip to Andromeda. The Andromeda galaxy. The view 311 00:20:59.720 --> 00:21:01.920 of our own galaxy from the outside is what I'd 312 00:21:01.960 --> 00:21:04.759 really like to see. Love to know how close our 313 00:21:04.759 --> 00:21:07.640 models are, just to make sure you got the color right, 314 00:21:08.119 --> 00:21:11.839 the color, how many spiral arms it's got? You know what? 315 00:21:12.119 --> 00:21:15.720 Don't we know that? No, not really. We think it's 316 00:21:15.720 --> 00:21:20.359 a forearm spiral, which is quite unusual. So you know, 317 00:21:20.480 --> 00:21:22.519 there's a there's a bar across the middle what we 318 00:21:22.599 --> 00:21:24.400 call a bar in the galaxy, not one you lean 319 00:21:24.480 --> 00:21:27.839 up against, but one that you you know, a bit 320 00:21:27.960 --> 00:21:30.440 like a rod or something like that. That's that's made 321 00:21:30.440 --> 00:21:33.160 of stars. And from each end of the bar, it 322 00:21:33.200 --> 00:21:35.720 looks as though there are two spiral arms that emerge. 323 00:21:36.119 --> 00:21:38.680 And that's based on mapping that we can do from 324 00:21:38.720 --> 00:21:40.680 the inside of the galaxy. But just imagine what it 325 00:21:40.720 --> 00:21:42.400 would look like if you're on the outside of it. 326 00:21:42.640 --> 00:21:47.960 Yeah, yeah, that's a great Yeah. I'd never contemplate a depth. 327 00:21:48.000 --> 00:21:49.880 To be honest, I know I have mentioned it before. 328 00:21:50.480 --> 00:21:55.400 I'd probably go further. I'd probably like to sort of 329 00:21:55.400 --> 00:22:02.799 get right away from our rum I suppose galactic cluster 330 00:22:03.279 --> 00:22:08.559 and look at the whole thing. I mean, I don't 331 00:22:08.599 --> 00:22:11.759 know how to explain it, but I'd like to be 332 00:22:11.839 --> 00:22:15.279 able to have in my view Andromeda and the Milky 333 00:22:15.319 --> 00:22:18.519 Way and whatever else is in the vicinity. You know, 334 00:22:20.039 --> 00:22:25.240 I'm assuming there are great voids between galaxy clusters, and 335 00:22:25.319 --> 00:22:27.160 I'd like to get out into one of them looking 336 00:22:27.160 --> 00:22:30.160 back at our galaxy cluster. I suppose that's what I'm saying. 337 00:22:30.240 --> 00:22:32.920 I think that would be fascinating just to see it 338 00:22:32.960 --> 00:22:35.279 all in one. 339 00:22:36.319 --> 00:22:41.480 Yes, yes, I think so. We're the Milky Way and 340 00:22:41.519 --> 00:22:43.759 the Andromeda Galaxy are the two biggest members of what 341 00:22:43.759 --> 00:22:48.720 we call the local Group, which is about thirty galaxies thereabouts. 342 00:22:49.319 --> 00:22:52.960 The next biggest one is the Triangular Galaxy, and then 343 00:22:53.000 --> 00:22:55.720 there's lots of small stuff. But we're part of a 344 00:22:56.039 --> 00:22:59.599 bigger cluster. I think it's a Virgo cluster that we're 345 00:22:59.640 --> 00:23:04.400 part of. I'm shocking it not remembering that that we're 346 00:23:04.720 --> 00:23:06.160 a little bit of that. It was certainly one of 347 00:23:06.160 --> 00:23:08.640 the bigger galaxy clusters we're part of as well. So 348 00:23:08.720 --> 00:23:11.799 you want to get right outside that and see what 349 00:23:11.839 --> 00:23:13.759 it looks like and be able to point to our 350 00:23:13.759 --> 00:23:17.240 Milky Way and say that's fled. Yeah. 351 00:23:17.359 --> 00:23:20.440 Yeah, I mean that's probably very un exciting to most people. 352 00:23:20.440 --> 00:23:23.119 I'm sure others have thought, oh, okay, well, if I 353 00:23:23.119 --> 00:23:25.119 could get a one G drive, what I would do 354 00:23:25.279 --> 00:23:31.079 is this, Maybe they can let us know. But you know, 355 00:23:31.160 --> 00:23:33.279 if we get achieved one G drive, it would make 356 00:23:33.319 --> 00:23:36.720 travel around the Solar System pretty schmick, wouldn't It is? 357 00:23:38.000 --> 00:23:42.880 It's it is. It's a nice concept because you you 358 00:23:42.960 --> 00:23:46.880 do two things. You give your spacecraft a long period 359 00:23:46.920 --> 00:23:50.279 of constant acceleration. But if you make it one G, 360 00:23:50.519 --> 00:23:54.200 then you've you've also provided your spacecraft with artificial gravity. 361 00:23:55.559 --> 00:23:58.680 So it means that everybody you know can stand upright 362 00:23:58.720 --> 00:24:01.880 on the bottom of the spacecraft as it's accelerating. Yeah, 363 00:24:02.319 --> 00:24:05.880 the end away from the the end of away from them, sorry, 364 00:24:05.920 --> 00:24:07.599 the way the end away from the point a bit 365 00:24:08.720 --> 00:24:14.720 that the bottom of your capsule that the acceleration would 366 00:24:14.839 --> 00:24:17.640 would mean that you were you were actually kept there 367 00:24:18.400 --> 00:24:20.839 exactly the same weight as you have on Earth. And 368 00:24:20.880 --> 00:24:22.839 then if you switched it around to slow down at 369 00:24:22.839 --> 00:24:24.960 the other end of your trip, you'd have one G 370 00:24:25.960 --> 00:24:29.759 also decelerating it. It's a really neat idea, if ever 371 00:24:29.839 --> 00:24:30.880 it can be made to work. 372 00:24:31.200 --> 00:24:32.400 Do you think it could work? 373 00:24:34.200 --> 00:24:38.640 Yes, well it could, but the main issue is sustaining 374 00:24:38.680 --> 00:24:41.240 it for a long period. That's why it's something that 375 00:24:41.279 --> 00:24:42.200 we haven't done yet. 376 00:24:43.640 --> 00:24:45.799 Maybe ion drive engines. 377 00:24:45.440 --> 00:24:47.559 That sort of thing. That's why that's the kind of 378 00:24:47.559 --> 00:24:48.519 thing that people think of. 379 00:24:49.279 --> 00:24:52.920 Yeah, could be interesting. Thank you, Rusty. As always you 380 00:24:52.920 --> 00:24:56.279 you pulled one out of the big black box. It's 381 00:24:56.960 --> 00:24:59.039 he's always got a bit of a curve ball for us. 382 00:24:59.079 --> 00:25:03.599 Has Rusty nice to hear from you. That is the 383 00:25:03.720 --> 00:25:06.960 end of this particular episode. If you would like to 384 00:25:07.000 --> 00:25:10.920 ask questions of Fred by all means, go to our 385 00:25:10.920 --> 00:25:14.799 website spacenuts podcast dot com. Spacenuts dot io is the 386 00:25:14.839 --> 00:25:17.599 other url. I'll both take you to the same place. 387 00:25:18.000 --> 00:25:21.640 You just click on the tab at the top and 388 00:25:22.039 --> 00:25:23.799 when you go in there, it gives you the option 389 00:25:23.880 --> 00:25:26.000 to send us a text or audio question. 390 00:25:26.079 --> 00:25:26.640 If you've got a. 391 00:25:26.599 --> 00:25:29.759 Device with a microphone, it's as easy as saying, Hi, 392 00:25:29.839 --> 00:25:33.559 I'm Fred from Sydney and I want to know and 393 00:25:33.880 --> 00:25:37.039 awhere you go. And if you're not named Fred, you 394 00:25:37.079 --> 00:25:39.759 can send us questions to just tell us who you 395 00:25:39.799 --> 00:25:43.799 are and where you're from, and we'd love to hear 396 00:25:43.839 --> 00:25:46.759 from you, especially if you've contemplated sending a question and 397 00:25:46.799 --> 00:25:49.640 you've been a bit reluctant. There are no dumb questions 398 00:25:49.680 --> 00:25:53.200 in astronomy and space science, so yeah, please please do 399 00:25:54.000 --> 00:25:57.200 get onto our website and send us some questions asap. 400 00:25:58.400 --> 00:25:59.960 We're done, Fred, thank you very much. 401 00:26:01.279 --> 00:26:04.640