A Challenge-Response Protocol for ITC Authentication

September 06, 2014

After publishing A Crypto Protocol for ITC Authentication, two things came to my attention: the general lack of interest on the side of parapsychology community, and the amount of (good) questions and feedback among non parapsychology researchers.

As I was inquired about ITC image phenomena [1] authentication, I want to propose another protocol. It resembles cryptographic authentication, where a hard problem is presented, and an answer is expected (in fact, it’s the exact reverse of crypto challenge-response, cause the challenger doesn’t know the answer beforehand).

In a non-economic sense, it’s the inverse of a POW system: the proof of work must not be feasible on the proposer side. But it should be checkable, once an answer is given.


From A Crypto Protocol for ITC Authentication:

ITC phenomena authentication should rely more on the process side of things, and less on the value of what one claims. Mathematics is a good tool for this kind of job

Paranormal digital evidence (photos, audio files, and recorded films) impose a burden on the side of whoever claims their legitimacy: a trusted third-part must issue an opinion for authentication.

In the aforementioned article, I focused more on a way to help paranormal researchers stand on their claims, based on the fact that their digital files could be enrolled in a strict authenticated timeline (immensely helping the forensic work).

But images impose a more subtle problem: CGI. I’m not saying audio can’t be faked. Advanced computational methods, like hidden Markov models, are known to deliver extremely good results for speech synthesis and recognition (to the point that they can be used to bypass security systems; researchers had to develop countermeasures to avoid false positives in biometric authentication). Besides that, paranormal videos carry a subjective “weight”: that’s something we see. Sight is one the most valued senses. And is subject to known psychological effects (like pareidolia), explored in techniques like Rorschach test.

To overcome subjective issues, I’ll strive to keep the protocol on measurable boundaries.


First of all, let’s clarify a few points about how trans photos and videos are produced.

Usually, a paranormal researcher points the camera to a background (with or without supporting lights/films), and starts the capture. A feedback loop is the method of choice sometimes. In any case, the expected outcome is some kind of artificial change, detectable by visual inspection of each photo (or each recorded frame of resulting footage).

As the theory underlying these insertions goes, the modifications are made possible by sophisticated energy from other dimension(s). Even when dealing with trans-images from deceased ones, we’ll assume that the process is based on (vastly) superior technology.

This is a strong idea, for sure, cause the existence of intelligent life outside our physical realm is implied.


A Crypto Protocol for ITC Authentication note #1 discussed an important point about paranormal files: content semantics.

What if we could extend this idea to images, avoiding DSP elements (like filters and frequencies), and focusing on the meaning of what is recorded, instead of its underlying digital traits?

Here lies the novel idea [2] : what about challenging the Communicators with some mathematical problem, and try to get a response? Math has two immediate advantages: as a priori knowledge, it is expected to be universal. And it introduces quantifiable limits (later on, we’ll see how this is important).

A trivial example will make the approach more clear. Let’s suppose we employ the following image as the background of an ITC session:

alt graphical Pythagorean theorem challenge Figure 1 - a graphical challenge: b2 + c2 = ?

We could expect a paranormal image insertion, with something like this:

alt graphical Pythagorean theorem Figure 2 - a graphical response: b2 + c2 = h2

Why? There’s evidence that Babylonian mathematicians knew Pythagoras’ theorem. Further, above right triangles were built with the Rule of 3-4-5. Even very old societies knew how to use the 3:4:5 ratio to create right angles (were they taught by ancient aliens? [23]).

As we’re (supposedly) dealing with exceptional Intellects, capable of manipulating space and time, a basic geometric fact should probably be known by their science.

At this point, one may ask: “how silly triangles can help to prove that trans-images are not frauds, even if children can develop them using the right software?”

This was a “warm up” discussion. To prove something so spectacular as the reality of paranormal images, this challenge-response approach will be leveraged, but in a slightly ingenious mode: we’ll suggest the “impossible”.


There are hard problems in mathematics. For example, in computer science, there is an intractable class of problems. Solving them could take, in years, the same order of magnitude as the age of the universe! In this way, really tough propositions - like intractable problems for our computers - could make excellent paranormal challenges. On a practical standpoint, they are hard enough for our current technology to answer in any reasonable window of time.

As we assumed that we were dealing with exceptional technology, responses of problems theoretically open to fast resolvability only by very advanced computational knowledge are true proofs that an allegedly paranormal footage is not a digital fraud (developed by an unscrupulous human being, or any human being at all).


Universal math aside, there’s the obstacle of which notation can be understood. If this was not the case, it would be much more simple to just challenge the Communicators with a really huge (special) composite number - like Google’s public-key - and ask them for the (unknown) prime factors [3]. Or ask for SHA-3 hash collisions (guaranteed by pigeonhole principle).

A geometric challenge was not chosen at random. If even Earth is a “Tower of Babel”, we shall encode the challenge graphically, avoiding notational problems as much as possible. The ideal challenge, then, would be an intractable math problem, representable graphically in a suggestive form.

One of the major open problems in computer science is that of P versus NP [4]. If NP is not the same as P (a fact widely believed), NP-complete problems are intractable in practice.

On the opposite camp, there are brilliant people like Donald Knuth, who believes P equals NP. But still in this case - at least for him - there would be no practical advantages (finding solutions to those problems would still be really hard).

Informally, NP-completeness captures the idea that some problems, whose answers can be quickly verified by a computer, can’t also be quickly found by an algorithm (the time required to solve them increases disproportionately as the problem grows).

Graph coloring could be one good candidate for a challenge. In its simplest formulation, a way of coloring the vertices of a graph must be found, such that no two adjacent vertices share the same color.

Two small Petersen graphs are showed below, to illustrate a challenge (on the left), and one possible response (on the right). We’re dealing with a reduced number of vertices (the 10 little circles, in a k-coloring scheme) and edges (the 15 black lines).

alt Petersen graph Figure 3 - Petersen graph 3-coloring
(Public Domain, Wikimedia Commons)

This harmless appearance should not fool the reader. Solving graph coloring in general isn’t a small feat. What seems like childish drawing encompasses a very complex task [5]. Also, as an instance of an NP-complete problem, every problem in NP is reducible/equivalent to it in polynomial time (i.e., it’s representative of a whole class of hard problems).

For larger instances, approximation algorithms offer little realistic advantages. And heuristics can be rendered useless, with just a bit of tedious work.


A very ingenious protocol was presented here. Once again, in a very informal manner. A lot of assumptions were made, based on overwhelming ITC records from recognized researchers [6].

Coupled with timeline support protocols, it may help paranormal researchers prove [7] (on a very quantitative basis) that trans image phenomena outcomes are produced by technology/knowledge outside our current science reach. And, as such, can’t always be the result of mere frauds.

[0] - I believe ITC is real, having experienced it;
[1] - I’ll keep referring to (trans/paranormal) videos, photos, and images interchangeably;
[2] - Never seen it before; contact me if any credit is due (and I’ll rectify);
[3] - Unknown to paranormal researchers and outside watchers; the factors are probably inside a Google’s HSM;
[4] - If you know the answer, claim your US $1,000,000 prize;
[5] - No special cases considered (the harder the problem, the better);
[6] - People like Sonia Rinaldi, from IPATI;
[7] - As with any ITC result, it’s up to the Communicators to decide if this endeavor deserves any collaboration;
[23] - “If at first the idea is not absurd, then there is no hope for it.” (Albert Einstein);