Efficient quantum key distribution scheme with pre-announcing the basis

Jingliang Gao , Changhua Zhu and Heling Xiao

Published 27 March 2014 • Copyright EPLA, 2014

116 Total downloads

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State Key Laboratory of Integrated Services Networks, Xidian University — Xi’an 710071, China

Received 7 November 2013

Accepted 12 March 2014

Published 27 March 2014

Jingliang Gao et al 2014 EPL 105 60003

We devise a new quantum key distribution scheme that is more efficient than the BB84 protocol. By pre-announcing the basis, Alice and Bob are more likely to use the same basis to prepare and measure the qubits, thus achieving a higher efficiency. The error analysis is revised and its security against any eavesdropping is proven briefly. Furthermore we show that, compared with the LCA scheme, our modification can be applied in more quantum channels.

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As monumental works of Science Fiction, the stories of Pern are meant to entertain. Even though Anne consulted with Scientists and other experts to maintain factual consistencies, there are many instances where information in one book appears to contradict information in another. Anne’s loyal fans refer to these as «Anne-consistencies».

Additionally, Anne commissioned other authors to write «reference» books to go into more detail regarding the world of Pern. These books, The Dragonlover’s Guide to Pern and The Atlas of Pern, do provide much more detail. However, certain facts that they discuss are in direct conflict with what Anne has written in her novels.

One consistency, it appears, is that debates will go on, unresolved, forever.

Name Inconsistencies

Several character names have changed throughout the course of the series; perhaps most notably the character / T’ton; the Weyrleader of Fort Weyr at the end of the Eighth Pass, whose name was changed without explanation to T’ron in all subsequent material. This can be considered a simple retcon, although in a few cases this can be explained in the story — for instance, T’ron could be said to have changed his name for some reason.

  • Jaxom and Felessan (Dragonquest)
  • Readis (Dolphins of Pern)
  • G’dened (Skies of Pern)
  • Sebell (Masterharper of Pern, [Dragonsinger)
  • In certain editions of Dragonsdawn, Kitti Ping is said to be the grandmother of Wind Blossom, but in other editions and Dragonsblood, she is Wind Blossom’s mother. According to Todd McCaffrey, this change occured during the writing of Dragonsblood, where UK editors questioned the relationship between the two, and Anne McCaffrey decided that their relationship better suited that of a mother and daughter. [1]
  • In Dragonflight, Larth — Lytol’s deceased dragon — is said to have been a green dragon, but also male. In all subsequent material, Larth was stated to have been a brown dragon.
  • In Dragonflight, F’lar states that Moreta was a famous Weyrwoman from Ruatha Hold who had the ability to «hear all dragons». However, Moreta: Dragonlady of Pern states that Moreta was from Keroon Hold, and has no such ability. According to an interview with Anne McCaffrey that was referred to in the Atlas of Pern, some famous names were re-used, and Karen Wynn Fonstad speculated in the Atlas that there may have been a second Moreta who was from Ruatha Hold and had the ability to hear all dragons, and that the two Weyrwomen were mistaken for the same person over time. In Nerilka’s Story, Alessan and Nerilka; the Lord and Lady Holder of Ruatha Hold, name their first daughter Moreta. This Moreta could be the Ruathan Weyrwoman who could hear all dragons.
  • L’rian goes Between with Danorth in Dragonheart, yet is mentioned among one of those restraining S’ban in Dragongirl.
  • In Dragonflight, Larth is said to have died during an accident in the Spring Games where S’lel’s Tuenth emerged from Between] flaming and fatally burnt him along his side. In Masterharper of Pern, F’lon states M’ridin’s Spakinth was the flaming dragon, and that it took place during a drill. Confusingly, M’ridin was not the rider of Spakinth; C’rob was — M’ridin’s dragon was Cortath. It should be noted that F’lon was drinking wine when he shared this information, so he may have mixed up the name of either dragon or rider.
  • Towards the end of Dolphins of Pern, Toric of Southern Hold is disciplined by the Lord Holders of the Northern Continent; including Oterel of Tillek Hold and Begamon of Nerat Hold. Later on, Oterel is one of the many people who meet Readis when it is decided to establish a Dolphineer’s Hall. This is a massive error, as both of these Lord Holders were replaced in All the Weyrs of Pern; Oterel died and was succeeded by his son Ranrel, and Begamon was stripped of his title and banished to the Eastern Ring Islands for his role in the attempted kidnap of Masterharper Robinton, and was succeeded by his brother Ciparis. It can be safely assumed that Ranrel and Ciparis attended the significant events instead.
  • In Dragonsblood, D’mal and Nara are the Weyrleaders of Fort Weyr during the late First Pass, yet the text in Dragonheart states they were the Weyrleaders immediately before K’lior and Cisca.
  • In All the Weyrs of Pern, N’ton’s dragon Lioth is mistakenly called Monarth; which is the name of T’gellan’s dragon.
  • In Sky Dragons, T’rennor’s green Kisorth is repeatedly confused with V’lex’s green Sarinth.
  • Robinton is retconned in The Masterharper of Pern, as he speaks to dragons his entire life. In earlier books he is beyond gratified every time a dragon speaks to him and is very surprised and alarmed at times when it happens. If he grew up being able to speak to any dragon at will.. it does not make sense when compared to the Dragonrider Trilogy.
  • At the end of Dolphins of Pern; Readis dubs his proposed hold «Kahrain Hold», after he is told that was the ancient name for the place. However, Readis’ site is actually located on the Rubicon River, in between Cathay and Araby Provinces; Kahrain Province being the large peninsula which Cove Hold is located on. This was later fixed in the updated version of The Dragonlovers’ Guide to Pern, which listed the name as «Rubicon River Hold».

The information that Telgar Weyr was built by the Sixth Pass is not mentioned in any of the novels covering this time; instead, it came from an interview with Anne McCaffrey (referenced in the Atlas of Pern); giving this as the reason for Fort Weyr flying Thread over Crom Hold.

While this could be explained as the result of the Weyr borders being different in the Sixth Pass, or Fort Weyr aiding Telgar Weyr for some unknown reason, it could also be that Telgar Weyr was abandoned at some point in time — similar to the abandoning of Igen Weyr in the Second Interval — and had only recently been re-established by this point.

In an interview, Anne McCaffrey stated that this was the

Since the exterior buildings were later shown being built in the First Interval, it could be that the changes noted by Capiam were renovations, or additions to the existing buildings.

It could be said that F’lar was referring to an addition to the Telgar Hold complex, instead of the main Hold building.

This is easily explained as the result of records b

Fort Weyr, Benden Weyr, High Reaches Weyr, Igen Weyr, Ista Weyr, Telgar Weyr. However, the short story The Second Weyr depicts Ista Weyr and Telgar Weyr being established as Weyrs alongside Benden Weyr, with the locations of High Reaches Weyr and Igen Weyrbeing noted for later dates. It is not clear whether the It should be noted, however, that the Ista Weyr and Telgar Weyr sites were being used by the dragonriders long before the establishment of Benden Weyr; which was still considered «the Second Weyr» despite this. This could suggest that Ista Weyr and Telgar Weyr were occupied, but not formally established as Weyrs until after High Reaches Weyr and Igen Weyrwere settled. Alternatively, the spread of settlements across the Northern Continent might have forced the dragonriders to abandon the Ista Weyr and Telgar Weyr sites in favour of choosing sites at High Reaches Weyr and Igen Weyr that were nearer to the settlements.

Fax’s Seven Holds

  • High Reaches Hold
  • Crom Hold
  • Nabol Hold
  • Keogh Hold (Minor Hold; beholden to Nabol Hold)
  • Balen Hold (Minor Hold; beholden to High Reaches Hold)
  • Riverbend Hold (Minor Hold; beholden to High Reaches Hold)
  • Ruatha Hold

(In earlier novels, Fax was said to have originally been the Lord Holder of Nabol Hold.)

  • High Reaches
  • Crom Hold
  • Radharc Hold (Minor Hold; beholden to Tillek Hold)
  • Keogh Hold (Minor Hold; beholden to Nabol Hold)
  • Nabol Hold
  • Unknown Minor Hold
  • Ruatha Hold

NOTE: In earlier novels, Fax is listed as being the Lord Holder of Nabol Hold. This was later retconned.

In both cases it is not entirely clear why Fax invaded Holds that would technically be under his control as Lord Holder — such as Riverbend Hold — although it could suggest the Holders resisted his control, or it could be that Fax simply wanted to have greater control over particularly productive Holds.

In The Masterharper of Pern, Fax is shown to have invaded Keogh Hold — beholden to Nabol Hold — before invading Nabol Hold; perhaps to get a base in Nabol. Despite now being Lord Holder of Nabol, Fax may have decided to keep his title as holder of Keogh Hold — which would make sense, considering his attitude in Dragonflight that all his

Fax is also mentioned in this version as having invaded Ogren Hold and Lewis Hold some time after capturing Radharc Hold. Since these holds would already have been under his control as they were beholden to High Reaches (like Balen and Riverbend), it could be that they were against his rule.

In a number of the Pern novels, dates or character ages are given that occasionally contradict each other. As a part of creating accurate and detailed pages, the Pern Wiki has analysed and adjusted several dates to deal with these inconsistencies — and also mentioning the incorrect date along with the adjusted date.

This section lists the problems encountered throughout the Pern novels, and the steps taken to rectify the timeline.

Ninth Pass Inconsistencies

Rectified Timeline

The simplest solution — the option that fixes the most dating and age errors without too many changes to canon — is this;

  • The opening chapter of The White Dragon is shifted from 12PP to 10PP; meaning Jaxom spent five years at the Smithcrafthall instead of three.
  • All the Weyrs of Pern’s dates — beginning in 19PP and ending in 23PP — are ignored; Renegades of Pern, Dolphins of Pern and Skies of Pern’s dates for the same period of time — beginning in 17PP and ending in 21PP — are used instead.
  • All lines that contradict this timeline ignored as simple inconsistencies — problems such as Jaxom & Felessan’s age in Dragonquest, contradictory dates in The White Dragon,Readis (II)’s age in Dolphins of Pern and the length of Shankolin’s imprisonment.
  • F’lessan’s being two years below the age for candidacy when Impressing Golanth acknowledged — perhaps either nepotism on F’lar and Lessa’s part, or the result of a shortfall of candidates that turn.
  • Path’s first rising taking place after four turns instead of two acknowledged as being part of the story — likely Path being inadvertantly inhibited for some reason.

This creates the following timeline;

  • 2505-2508AL/2518-2521AAT (1PP) — Events of Dragonflight.
  • 2515AL/2529AAT (8PP) — Events of Dragonquest, Dragonsong and Dragonsinger.
  • 2517AL/2531AAT (10PP) — Jaxom flies Ruth for the first time.
  • 2518AL/2532AAT (11PP) — Events of Dragondrums.
  • 2519AL/2533AAT (12PP) — Events of The Girl Who Heard Dragons.
  • 2523AL/2537AAT (15PP) — Events of The White Dragon.
  • 2525AL/2539AAT (17PP) — Discovery of Aivas.
  • 2529AL/2543AAT (21PP) — Completion of Project Overkill; Death of Masterharper Robinton.
  • 2537AL/2551AAT (29PP) — Readis establishes Rubicon River Hold (incorrectly listed as Kahrain Hold)
  • 2539AL/2553AAT (31PP) — Events of The Skies of Pern.

In Dragonseye, set during the Second Pass, it states that no one has fire-lizard companions although in Todd McCaffrey’s Dragonsblood, set during the Third Pass, most of the population still has fire-lizards before the disease wipes them out and spreads to the dragons.

Efficient quantum key distribution scheme with pre-announcing the basis
Efficient quantum key distribution scheme with pre-announcing the basis Jingliang Gao , Changhua Zhu and Heling Xiao Published 27 March 2014 • Copyright EPLA, 2014 116 Total
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As monumental works of Science Fiction, the stories of Pern are meant to entertain. Even though…