Richard Feynman Updated 2024-12-15 +Created 1970-01-01
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Some of Feynman's key characteristics are:
  • obsession with understanding the experiments well, see also Section "How to teach and learn physics"
  • when doing more mathematical stuff, analogous obsession about starting with a concrete example and then generalizing that into the theory
  • liked to teach others. At Surely You're Joking, Mr. Feynman for example he mentions that one key problem of the Institute for Advanced Study is that they didn't have to teach, and besides that making you feel useless when were not having new ideas, it is also the case that student's questions often inspire you to look again in some direction which sometimes happens to be profitable
    He hated however mentoring others one to one, because almost everyone was too stupid for him
  • interest in other natural sciences, and also random art and culture (and especially if it involves pretty women)
Some non-Physics related ones, mostly highlighted at Genius: Richard Feynman and Modern Physics by James Gleick (1994):
Even Apple thinks so according to their Think different campaign: www.feynman.com/fun/think-different/
Feynman was apparently seriously interested/amused by computer:
Video 1.
Murray Gell-Mann talks about Richard Feynman's intentional anecdote creation
. Source. TODO original interviewer, date and source. Very amusing, he tells how Feynman wouldn't brush his teeth, or purposefully forget to wear jacket and tie when going to the faculty canteen where it was required and so he would use ugly emergency jacket the canteen offered to anyone who had forgotten theirs.
Video 2.
Murray Gell-Mann talks about Feynman's partons by Web of Stories (1997)
Source. Listener is likely this Geoffrey West. Key quote:
Feynman of course, as usual, put it in a form so that the common people could use it, and experimentalists all over the world now thought they understood things because Feynman had put it in such simple language for them.
Two official websites?
In 1948 he published his reworking of classical quantum mechanics in terms of the path integral formulation: journals.aps.org/rmp/abstract/10.1103/RevModPhys.20.367 Space Time Approach to nonrelativistic quantum mechanics (paywalled 2021)
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Super Mario 64 reverse engineering project Updated 2024-12-15 +Created 1970-01-01
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OMG, both of those just fucking work on Ubuntu 20.04 with README instructions, it is unbelievable, those people don't have lives. And it builds the ROM byte by byte equal from source!
There are a few different versions:
Tested with the USA ROM at sha1sum 9bef1128717f958171a4afac3ed78ee2bb4e86ce (you need a ROM to extract assets, which the project automates), which is also documented in the project itself: github.com/sm64-port/sm64-port/blob/6b47859f757a40096fedd6237f2bc3573d0bc2a4/sm64.us.sha1. Disclaimer: Ciro Santilli owns a copy of Super Mario 64.
The only dependency missing from Ubuntu packages is the IRIX QEMU user mode which they need for their tooling. The project also has a QEMU fork for that, and provide a working deb.
From this project it was also noticed that certain ROM releases were not compiled with optimizations enabled, presumably because as a release title the compiler had optimization bugs! www.resetera.com/threads/so-apparently-the-ntsc-build-of-mario-64-didnt-use-any-compiler-optimizations.166277/ But now they do have a working compiler, and by turning that switch FPS increases in certain levels!!!
It is good to know that this game will "never die".
Some quick stupid patches:
  • jump really high:
    diff --git a/src/game/mario.c b/src/game/mario.c
index 5b103fa..83c9f40 100644
--- a/src/game/mario.c
+++ b/src/game/mario.c
@@ -826,7 +826,7 @@ static u32 set_mario_action_airborne(struct MarioState *m, u32 action, u32 actio
         case ACT_JUMP:
         case ACT_HOLD_JUMP:
             m->marioObj->header.gfx.unk38.animID = -1;
-            set_mario_y_vel_based_on_fspeed(m, 42.0f, 0.25f);
+            set_mario_y_vel_based_on_fspeed(m, 200.0f, 0.25f);
             m->forwardVel *= 0.8f;
             break;
Interesting entry points:
  • src/game/game_init.c
TODO: enable the level select debug feature! tcrf.net/Super_Mario_64_(Nintendo_64)/Debug_Content#Classic_Debug_Display They actually shipped quite a few debug features into the retail game, and they have been reversed too. I tried this but it didn't work (or I don't know how to enable the level select menu):
diff --git a/src/game/main.c b/src/game/main.c
index 9e53e50..b7443a8 100644
--- a/src/game/main.c
+++ b/src/game/main.c
@@ -65,7 +65,7 @@ s8 sAudioEnabled = 1;
 u32 sNumVblanks = 0;
 s8 gResetTimer = 0;
 s8 D_8032C648 = 0;
-s8 gDebugLevelSelect = 0;
+s8 gDebugLevelSelect = 1;
 s8 D_8032C650 = 0;

 s8 gShowProfiler = FALSE;
The enhancements/ folder contains a few sample patches.
Figure 1.
Screenshot of mupen64Plus running on Ubuntu 20.04 emulating Super Mario 64 with the title screen hacked by Ciro Santilli based on the Super Mario 64 reverse engineering project
. The title was on a string, so the hack was trivial! The patch used was:
diff --git a/include/text_strings.h.in b/include/text_strings.h.in
index 749179b..626f87e 100644
--- a/include/text_strings.h.in
+++ b/include/text_strings.h.in
@@ -131,7 +131,7 @@
  */
 // Main Screens
 #define TEXT_MARIO _("MARIO") // View Score Menu
-#define TEXT_SELECT_FILE _("SELECT FILE")
+#define TEXT_SELECT_FILE _("HACKED BY CIRO")
 #define TEXT_CHECK_FILE _("CHECK FILE")
 #define TEXT_COPY_FILE _("COPY FILE")
 #define TEXT_ERASE_FILE _("ERASE FILE")
Some tutorials of hacking it:
Video 1.
FIXING the ENTIRE SM64 Source Code by Kaze Emanuar (2022)
Source. Now that we have the source, modders like this are going nuts.
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Universal Turing machine Updated 2024-12-15 +Created 1970-01-01
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A Turing machine that simulates another Turing machine/input pair that has been encoded as a string.
In other words: an emulator!
The concept is fundamental to state several key results in computer science, notably the halting problem.
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User mode emulation Updated 2024-12-15 +Created 1970-01-01
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User mode emulation refers to the ability of certain emulators to emulate userland code running on top of a specific operating system, usually Linux.
For example, QEMU allows you to run a variety of userland ELF programs directly on it, without an underlying Linux kernel running.
User mode emulation is achieved by implementing System calls and special filesystems such as /dev manually on the emulator one by one.
The general tradeoff is that simulation is less acurate as it may lack certain highly advanced kernel functionality you haven't implemented yet. But it is much easier to run executables with it, and you don't have to wait for boot to finish before running, you just run executables directly from the command line.
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