Item #: SCP-155
Object Class: Euclid
Special Containment Procedures: SCP-155 is normally kept in a locked steel cabinet in its research area. No non-trivial computations may be done with SCP-155 without Overwatch approval. No non-halting problem may ever be run on SCP-155 (see Incident Report 155-A). Whenever SCP-155 is used for computations, it must be placed in its containment area, surrounded by 3 meters of lead. No personnel may be in the containment area at the time of program execution.
Description: SCP-155 is a 70 cm x 70 cm x 70 cm black box with 5 noticeable features. It has a steel aperture on one end, another on the other end, a button on another side, a small hole on the top, and a paper tape output on another side. The box weighs 200 kg. The black material it is covered with is an extremely dense non-molecular substance known to contain lead and iridium, among other elements. SCP-155 was found in ████████████████████. Its toughness made it the only item that remained usable or recognizable after ██████████. SCP-155 blocks all types of scans due to its material's density.
After its acquisition, SCP-155 was tested for several months before its function was recognized. SCP-155 takes a binary program in electric form through one of its apertures (a sticker labeled "Input" was attached to this aperture after this discovery). The program must be written in a previously-unknown binary language that was only discovered through trial and error. An assembly language was created for SCP-155 and a high-level language is in development.
Once a program is received and the button is pressed, SCP-155 starts the execution. SCP-155 starts slowly, but the speed increases asymptotically, approaching infinity as execution time approaches 8 minutes. As speed increases, SCP-155 begins to suck matter in through its top hole, likely for use as fuel. SCP-155 also begins to heat up and emit radiation, which increases proportionally with speed. While the radiation is negligible for almost all programs, it has on more than one occasion caused deaths. Once execution is finished, SCP-155 gives output both by sending it electrically through its other aperture and by printing it out on tape, if the output is less than 100 bytes.
Addendum: Incident Report 155-A
On ███████████████, Dr. █████████ input a non-halting program into SCP-155. At the time, it was believed to be a halting program, due to the unproven ██████████ Theorem. At execution time 7:59, SCP-155 emitted a massive burst of heat and light radiation, destroying its containment area and much of its research area and causing significant casualties. Dr. █████████ died in this incident.
Memo 155-1: "The personnel who attached the 'Crysis Capable Computer' sticker to SCP-155 has been reprimanded. Personnel are reminded that they must treat all SCP objects with the utmost respect, or else I will come down on them like a ton of bricks." - Dr. Klein