A method and apparatus for certification of facts introduces a certifier and a fact certificate into the fact-exchange cycle that enables parties to exchange trustworthy facts. Certification is provided to a fact presenter during the first part of the fact-exchange cycle, and verification is provided to the fact receiver during the last part of the cycle. To request a certification, a fact presenter presents the Certifier with a fact. In return, the certifier issues a fact certificate, after which the fact presenter presents the fact certificate to the fact receiver instead of presenting the fact itself. The receiver inspects the received certificate in order to evaluate the fact's validity and trustworthiness. For some facts and notions of verification, the certificate is sufficient and its inspection does not require any communication. For others, the receiver requests a verification service from the Certifier in order to complete the verification.
Please help me write a proper abstract based on the patent claims. CLAIM: 1. A computer-implemented method, comprising: sending an observed fact corresponding to an event from any of a fact presenter and an observer to a fact certifier for certification of the observed fact, wherein the observed fact originates from the observer, and wherein the observer is a witness to the observed fact; and receiving a fact certificate at the fact presenter from the fact certifier, responsive to a certification by the fact certifier of the observed fact sent from the fact presenter or the observer to the fact certifier; wherein, after receipt of the fact certificate at the fact presenter, transmitting fact information directly from the fact presenter to a fact receiver; wherein the transmitted fact information includes any of the observed fact and the received fact certificate; and wherein the fact receiver is enabled to establish that the event is valid, using the observed fact or the fact certificate. 2. The method of claim 1, wherein a level of trust between the fact receiver and the observer enables the fact receiver to trust any of the fact and the fact certificate. 3. The method of claim 1, wherein the observer is any of a person or a measurement device. 4. The method of claim 1, wherein the sent observed fact includes a timestamp that certifies timeliness of the observed fact. 5. The method of claim 1, wherein the observer is registered to operate on behalf of the fact presenter. 6. The method of claim 1, wherein the observer has previously been registered with the fact certifier to operate on behalf of the fact presenter. 7. The method of claim 6, wherein the registering of the observer with the fact certifier includes: assigning the observer with a unique observer identifier (ID), storing the unique observer ID in a database, and providing a token to the observer that allows proof of the identity of the observer when presenting information. 8. The method of claim 1, further comprising: broadcasting the fact certificate from the fact presenter to a witness network that includes one or more trusted witnesses; wherein a level of trust between the fact receiver and one or more of the trusted witnesses enables the fact receiver to trust any of the fact and the fact certificate. 9. The method of claim 8, wherein the fact receiver is enabled to search the witness network to find a particular trusted witness that is trusted by the fact receiver, and to direct a verification request to the particular trusted witness to establish that the event is valid. 10. The method of claim 1, wherein the observed fact must be submitted to the certifier within a time window for acceptance by the fact certifier. 11. The method of claim 1, wherein the transmitting any of the fact and the fact certificate to the fact receiver comprises: transmitting the certified fact and the fact certificate from the fact presenter to the fact receiver; wherein the fact receiver receives both the fact and the fact certificate; and wherein the fact receiver enabled to establish that the fact is valid, using both the fact and the fact certificate. 12. The method of claim 1, wherein the event includes any of a physical event, a measurement, an electronic transaction and a financial transaction. 13. The method of claim 12, wherein the physical event includes any of at least two people being in a common location concurrently, a person being close to an object at a given time, and at least two objects being in a common place concurrently. 14. The method of claim 12, wherein the measurement is performed by a measurement device. 15. The method of claim 14, wherein the measurement device is any of a speed measurement device, a sensor, a camera, and an audio recorder. 16. A computer-implemented method, comprising: maintaining a database of trusted observers at a fact certifier; registering an observer at the fact certifier; adding the registered observer to the database of trusted observers; receiving an observed fact corresponding to an event from any of a fact presenter and the registered observer, for certification of the observed fact, wherein the observed fact originates from the registered observer, and wherein the registered observer is a witness to the observed fact; and sending a fact certificate to the fact presenter from the fact certifier, responsive to a certification by the fact certifier of the received observed fact; wherein, after receipt of the fact certificate at the fact presenter, the fact presenter is enabled to transmit fact information directly to a fact receiver, wherein the transmitted fact information includes any of the observed fact and the fact certificate; and wherein the fact receiver is enabled to establish that the event is valid, using the observed fact or the fact certificate. 17. The method of claim 16, wherein the registering of the observer with the fact certifier includes: assigning the observer with a unique observer identifier (ID), storing the unique observer ID in the database of trusted observers, and providing a token to the observer that allows proof of the identity of the observer when presenting information. 18. The method of claim 16, wherein a level of trust between the fact receiver and the registered observer enables the fact receiver to trust any of the fact and the fact certificate. 19. The method of claim 16, wherein the registered observer is any of a person or a measurement device. 20. The method of claim 16, wherein the received observed fact includes a timestamp that certifies timeliness of the observed fact. 21. The method of claim 16, wherein the registered observer can operate on behalf of the fact presenter. 22. The method of claim 16, wherein the fact presenter is enabled to broadcast the fact certificate to a witness network that includes one or more trusted witnesses; wherein a level of trust between the fact receiver and one or more of the trusted witnesses enables the fact receiver to trust any of the fact and the fact certificate. 23. The method of claim 22, wherein the fact receiver is enabled to search the witness network to find a particular trusted witness that is trusted by the fact receiver, and to direct a verification request to the particular trusted witness to establish that the event is valid. 24. The method of claim 16, wherein the observed fact must be submitted to the fact certifier within a time window for acceptance by the fact certifier. 25. The method of claim 16, wherein the transmitting any of the fact and the fact certificate to the fact receiver comprises: transmitting the certified fact and the fact certificate from the fact presenter to the fact receiver; wherein the fact receiver receives both the fact and the fact certificate; and wherein the fact receiver is enabled to establish that the fact is valid, using both the fact and the fact certificate. 26. A computer-implemented method, comprising: sending a deduced fact from a fact presenter to a trustee that is is trusted by the fact presenter, wherein the deduced fact includes private information; sending a secure digest of the deduced fact from the fact presenter to a fact certifier for certification of the deduced fact, wherein the digest does not disclose the private information; receiving a fact certificate at the fact presenter from the fact certifier; transmitting any of the fact and the fact certificate from the fact presenter to a fact receiver, wherein the fact receiver is enabled to establish that the fact is valid, using the fact or the fact certificate. 27. The method of claim 26, wherein the trustee is allowed to disclose a portion of contents of the deduced fact as set initially by the fact presenter. 28. The method of claim 26, wherein during a verfication of the deduced fact, the fact certifier obtains a full basis of a claim for the deduced fact in a digest form. 29. The method of claim 26, wherein during a verfication of the deduced fact, the fact certifier knows a universal fact identifier of each fact upon which the deduced fact is based 30. The method of claim 26, wherein the fact receiver is enabled to choose a number of private facts to make a verification request to the trustee. 31. The method of claim 30, wherein in response to the verification request, the trustee is enabled to reveal a full certificate to the fact receiver. 32. The method of claim 30, wherein because the number of private facts are chosen by the fact receiver, the fact receiver can trust other information related to the deduced fact that the fact receiver has not seen.